FOOD STUDY
Copyright by Underwood & Underwood, N. Y.
A FIELD OF SUGAR CAXE
The source of one of our important foods
FOOD STUDY
A TEXTBOOK IN HOME ECONOMICS
FOR HIGH SCHOOLS
BY
MABEL THACHER WELLMAN
,
ASSOCIATE PROFESSOR AND HEAD OF DEPARTMENT OF
HOME ECONOMICS IN INDIANA UNIVERSITY
FORMERLY INSTRUCTOR IN DIETETICS AND HOUSEHOLD
CHEMISTRY AT LEWIS INSTITUTE, CHICAGO
BOSTON
LITTLE, BEOWN, AND COMPANY
1920
Copyright, 1917,
BY LITTLE, BROWN, AND COMPANY.
All rights reserved
Co
MRS. ALICE PELOUBET NORTON
WHOSE TEACHING HAS BEEN THE
SOURCE OF INSPIRATION
OF THIS BOOK
43846-1
ACKNOWLEDGMENT
THANKS are due to John Wiley & Sons for the use of
starch cuts from Leach's "Food Inspection and Analy-
sis"; to Ginn & Company for the use of mold cuts from
Conn's "Bacteria, Yeasts and Molds in the Home";
to the University of Illinois Agricultural Experiment
Station for the use of illustrations of cuts of steak; to
Walter Baker & Company for permission to use the copy-
righted cuts of the coffee berry and cocoa bean ; to Mrs.
Janet McKenzie Hill for the use of illustrations from
"Cooking for Two" ; to Miss Lucy G. Allen for diagrams
from "Table Service" ; to the Hoosier Manufacturing
Company for floor plans ; to the Walker & Pratt Manu-
facturing Company for diagram of a coal stove; and to
the heirs of Miss Fannie Merritt Farmer for permission
to use important recipes from the "Boston Cooking-
School Cook Book."
FOREWORD TO THE TEACHER
HOME ECONOMICS is still so new a study that no apology
is necessary for placing another textbook in this subject
on the market. Many of the best books which are now
available obviously are intended for the benefit of the
teacher rather than for the student, while others are
little more than carefully selected collections of recipes.
The present work is an attempt to present a manual of
definite directions which will aid the student in her ad-
venture into the subject, but it is by no means intended
to supersede the teacher or to furnish material which
can be taught by one untrained in the subject.
As in physics and chemistry, there are principles in
cooking which are worthy of consideration, and, as in
any science, they should be taught from an inductive
standpoint. But, equally, no attempt at a completely
inductive course should be made. The accumulated ex-
periences of mankind can be used with benefit. To
show a cake, for example, to a student who knows noth-
ing of cooking, and let her guess the ingredients, the
methods of combining them, and the temperature used
in baking, and then to let her experiment until she pro-
duced a perfect cake, might teach cooking, but the road
would be long and arduous. On the other hand, here,
as in other sciences, sufficient discovery to arouse interest,
viii FOREWORD TO THE TEACHER
to enable the pupil to question understanding!;^ and to
give control of the situation, is of undoubted benefit and
leads on naturally to research.
Where inductive courses have failed, the reason has
been most often that the preparatory steps have been
omitted by the teacher, and the student has been set to
find out something when she has no knowledge of what
she has set out to find. Chance discoveries, of course,
find their applications later on, but this is not education.
The student needs to have clearly in mind the results
looked for, before she begins an experiment. This by no
means implies that the result itself should be known, for
then interest is dulled. References should be looked up
only after the practical work, or its chief value is lost.
If it is necessary to economize on time, where com-
parative results are to be obtained, as in making tea, the
experiments may be divided among the class so that
one student compares her results with those of her neigh-
bors. This distribution of work, however, is not possible
when preparing dishes which call for skill in handling
or involve some special principles in combining or in
cooking; but there is no reason why one student may
not prepare bean soup while her neighbor makes potato
soup. Such a practice often helps to impress underlying
principles. College classes have been known to finish
their course in cooking with the idea that a special recipe
was necessary for each kind of soup or cake, and without
knowledge of proportions which would tell them when a
recipe was outside the bounds of possibility. This is
the result of cooking entirely from recipes. On the
other hand, an error quite as bad is made when recipes
are never used.
The order of the topics in this book is not that of the
conventional cook book, nor is it based on the chief food
FOREWORD TO THE TEACHER ix
principles, but is a logical working out of the subject and
makes possible certain advantages in presentation, as the
early introduction of such subjects as meals and serving.
This gives opportunity for the economic study needed as
a basis for household management all too often omitted
from courses in home economics and also affords an
occasion for necessary repetition of work, if skill as well as
knowledge is to be acquired. Another excellent way to
introduce repetition is by contests, in which, for example,
the students not only try to see who can make the best
bread but also are required to judge the results and
show why one is more desirable than another. In this
way they learn standards of perfection otherwise difficult
to teach. Regulation "score cards" may or may not be
used for such work.
The laboratory notes should show clearly the results
obtained in all experiments and should also answer all
questions asked in the directions. Recipes may be
written here, or better, kept in card catalog form. It is
well to accustom the student to the handling of a cook
book, and familiarity with more than one is surely de-
sirable.
The divisions I, II, III, and the like do not mean
divisions of single lessons. The experiments and the
cooking presented in each chapter can be carried out in
a double period of an hour and a half. Following the
laboratory work of each chapter of the text is material
intended to be taken up in subsequent recitations. Double
periods are not needed for recitation. If the schedule
calls for them, part of the time may well be occupied in
writing up note books. A double period for laboratory
work and a single period for recitation form a unit of
work which may be given once in a week, or twice if
time permits.
X FOREWORD TO THE TEACHER
The questions at the end of the lessons are not in-
tended to be written up in the laboratory notes, as they
are often much too comprehensive. Neither are they
intended to be exhaustive. Their object is to show
the student the scope of the subject, to give definite
material to look for in the references, and to start the
student thinking.
The laboratory work may be extended indefinitely by
preparing under each section other dishes which are
similar in principle. (See list of supplementary laboratory
work.) For convenience in using supplies, other dishes
can be substituted for those mentioned. In jelly-making,
for example, crab apple and grape are the fruits given,
one chosen as a juicy fruit requiring the addition of
no water, the other needing water in its preparation;
any other fruits answering these requirements may be
substituted. Jelly-making, pickling, and preserving are
placed first in the course, not because it is the logical
order, but because autumn is the best time in the school
year to obtain the necessary fruits. An attempt has also
been made to consider the amount of skill required in
every process. For this reason the dough and batter
series has not been introduced directly after the first
study of starch, but has been placed after the meat and
vegetable work. Since a laboratory using many ovens
becomes exceedingly warm, the roasting of meat and the
baking of bread, cake, and pies are not left until the end
of the course, for the least possible hot work is desirable
at the end of the school year.
It has not seemed desirable to explain such processes
as how to break an egg, how to beat eggs, how to "fold"
in the whites, how to use a rolling-pin, and all the rest.
The teacher who shows the process can make it plainer
than any words can do.
CONTENTS
CHAPTER I
FRUIT
PAGE
Coddled Apples ; Apple Sauce ; class experiment (Spoiling
of Fruit) ; lesson on Fruit . . . . . 1
CHAPTER II
CANNING FRUIT
Canned Peaches ; class experiment (Cause of Fruit Spoiling) ;
lesson on Molds . ... * , . . . 7
CHAPTER III
JELLY
Apple and Grape Jelly ; Trial Jelly ; Experiments and Tests
for Jellying ; lesson on Principles of Jelly-making . . 13
CHAPTER IV
JELLY-MAKING
Repeated Extractions; class experiments (Food Preserva-
tives) ; class work (Cucumber Pickles) ; lesson on Yeasts
and Bacteria 19
xii CONTENTS
CHAPTER V
SWEET PICKLED PEACHES
PA6K
Class experiments (Micro-organisms); lesson on Micro-
organisms . . . . . . . . . . 25
CHAPTER VI
USE OP WATER IN COOKING
Boiled Potatoes ; Mashed Potatoes ; class experiment (Stages
of Boiling Water) ; lesson on Potatoes .... 30
CHAPTER VII
USE OP WATER IN COOKING
Boiled Eggs; Stuffed Eggs ; class experiments (Eggs) ; lesson
on Water 39
CHAPTER VIH
USE OP WATER IN COOKING
Poached Eggs ; class experiment (Solubility of Egg White) ;
class experiment (Correct Temperature for Poaching
Eggs) ; lesson on Eggs 46
CHAPTER IX
USE OP WATER IN COOKING
Cereal Breakfast Foods ; class experiment (Relation of Sur-
face to Evaporation) ; Cereal with Fruit ; class experi-
ments (Cereals) ; lesson on Cereal Breakfast Foods . 51
CHAPTER X
STARCH
Apple Tapioca; Boiled Rice; lesson on Starch . . . 56
CONTENTS xiii
CHAPTER XI
BICE AND INDIAN PUDDINGS
PAGE
Cost of Breakfast Foods; preparation of Rice Pudding,
Indian Pudding, and Crisped Cereals ; lesson on Cellu-
lose ; lesson on Mineral and Organic Salts ... 62
CHAPTER XII
REVIEW LESSON
Breakfast, preparation and serving; lesson on Setting the
Table . ... . . . ... 67
CHAPTER XIII
TEA
Marshmallow Wafers ; individual experiments (Green Tea) ;
class experiments (Black Tea) ; lesson on Tea . . 74
CHAPTER XIV
COFFEE
Cheese Wafers ; class experiments (Making Coffee) . . 79
CHAPTER XV
COCOA AND CHOCOLATE
Oatmeal Cookies ; class experiments (Making Cocoa) ; Pre-
paring Chocolate; lesson on Cocoa, Chocolate, Condi-
ments and Flavoring Extracts . . ... '. . . 83
CHAPTER XVI
FREEZING
Water Ices ; Sherbet ; class experiments (Freezing Mixtures) ;
Lemon Ice ; class work (Lemon Sherbet) ; lesson on
Freezing Mixtures 90
Xiv CONTENTS
CHAPTER XVII
RECEPTION
PAGE
Candied Fruit Peel; Marguerites; Sandwiches; lesson on
Receptions . . ... . . . .95
CHAPTER XVIII
COMBUSTION AND FUELS
Scalloped Potatoes ; class experiments (Fuels) ; lesson on
Combustion and Fuels 98
CHAPTER XIX
DRAFTS AND THE COAL RANGE
Baked and Stuffed Potatoes ; class experiments (Drafts) ;
lesson on Coal Stoves 104
CHAPTER XX
FLAME AND GAS STOVES
Chocolate Bread Pudding ; class experiments (Care of a Gas
Stove) ; lesson on Gas Stoves ; How to Read a Gas Meter 108
CHAPTER XXI
RADIATION AND CONDUCTION OF HEAT
Class experiments (Transmission of Heat) ; Scrambled Eggs
on Toast ; lesson on Fireless Cookers . . . . 114
CHAPTER XXII
CONVECTION OF HEAT
Class experiments (Transmission of Heat) ; Potato Salad ;
Broiled Bacon ; lesson on Hot-water Systems ; lesson on
Kitchen Ware . 118
CONTENTS XV
CHAPTER XXIII
REVIEW LESSON
PAGE
Second Breakfast ; Omelets, Fried Mush and Syrup ; lesson
on Table Manners . . - . -<.,..* . 122
CHAPTER XXIV
MEDIUM WHITE SAUCE
Class experiments (Starch) ; White Sauce ; Creamed Chipped
Beef on Toast ; lesson on Wheat . . I 28
CHAPTER XXV
THICK WHITE SAUCE
Salmon Croquettes ; Cheese Souffle* ; lesson on Bread Flour . 132
CHAPTER XXVI
STARCH
Class experiment (Comparison of Flour and Cornstarch);
Cornstarch Mold; Chocolate Sauce; Macaroni and To-
mato Sauce ; lesson on Cornstarch * , . 135
CHAPTER XXVII
CREAMED VEGETABLES
Class experiments (Effect of Heat on Starch) ; Peas and Car-
rots ; lesson on Canned Vegetables . . . . . 139
CHAPTER XXVIH
THIN WHITE SAUCE
Cream Soups : Celery and Potato ; lesson on Classification of
Vegetables .142
xvi CONTENTS
CHAPTER XXIX
SCALLOPED VEGETABLES
PAGK
Class experiment (Mineral Ash in Vegetables) ; Cooking
Cabbage or Onion ; Cream Soup ; lesson on Vegetables . 146
CHAPTER XXX
GREEN VEGETABLES
Spinach ; Lettuce ; class experiments (Freshening of Green
Vegetables) ; French Dressing ; Sour Cream Dressing ;
lesson on the Amount of Food Necessary . . . 150
CHAPTER XXXI
SWEET-FLAVORED VEGETABLES
Squash; Buttered Beets; class experiment (Sugar Test);
lesson on Cane and Beet Sugar 158
CHAPTER XXXII
CANDIES
Class experiment (Stages in Sugar Cooking) ; class experi-
ment (Crystallization of Sugar) ; lesson on Carbohydrates 162
CHAPTER XXXIII
MEAT CAKES WITH CREAMED TTJRNIPS
Class experiment (Tests with Meat) ; class experiment
(Structure of Meat) ; Broiled Meat Cakes ; lesson on
Meat . 168
CHAPTER XXXIV
TENDER MEAT
Roast Beef ; Broiled Beefsteak and Corn Pudding ; class ex-
periment (Cooking Meat) ; lesson on Cuts of Beef and
Principles of Cooking Meat * , * .. ,. . . 175
CONTENTS XV11
CHAPTER XXXV
BEEF STEW
PAGE
Class experiments (Cooking Meat) ; Beef Stew and Dump-
lings ; class experiment (Keeping Meat Tender) ; lesson
on Meat Inspection . . . . .. . . . 179
CHAPTER XXXVI
LEFT-OVERS
Southern Spoon Bread ; lesson on Proteins . . . 183
CHAPTER XXXVII
MEAT SOUPS
Class experiment (Soluble Contents of Meat) ; class experi-
ment (Use of Bones in Soup) ; lesson on Meat Soups . 188
CHAPTER XXXVIII
GELATINE DISHES
Lemon Jelly; Snow Pudding; Bavarian Cream ; class experi-
ments (Gelatine) ; lesson on Gelatine . . . . 191
CHAPTER XXXIX
REVIEW LESSON
Dinner; Split-Pea Soup ; Spanish Cream ; lesson on Styles of
Serving . . . ^ . , ... 194
CHAPTER XL
POULTRY
Roast Chicken ; Fried Chicken ; class work (Weighing, Dress-
ing, Trussing, Roasting, and Frying Chicken) ; lessons
on Poultry and the Digestibility of Meat * . . 198
xviii CONTENTS
CHAPTER XLI
FISH
P4M
Baked Fish ; Boiled Fish with Egg Sauce ; Scalloped Fish ;
Stewed Tomato ; lesson on Composition and Digestibility
of Fish 202
CHAPTER XLII
OYSTER STEW FISH CHOWDER
Class experiment (Cooking Oysters) ; Preparation of Oyster
Stew and Fish Chowder ; lesson on Oysters . . . 207
CHAPTER XLIII
REVIEW LESSON
Dinner; Tomato Soup; Jellied Prunes; lesson on The
Dining Room 213
CHAPTER XLIV
POP-OVERS
Making Pop-overs; class experiments (Measuring Sifted
Flour ; White of Egg in Hot Fat) ; lesson on Flour
Mixtures 216
CHAPTER XLV
APPLE FRITTERS
Class experiment (Principle of Leavening) ; Apple Fritters ;
lesson on Leavening 220
CHAPTER XLVI
SOUR MILK GRLDDLECAKES
Class experiment (Soda as a Leavening Agent) ; Sour Milk
Griddlecakes ; lesson on Soda . v 222
CONTENTS XIX
CHAPTER XLVH
LEAVENING
PAGE
Sweet Milk Griddlecakes ; Sponge Cake; class experiment
(Baking Powder) ; lesson on Baking Powders . . 226
CHAPTER XLVIII
MUFFINS
Making Muffins ; class experiment (Weight of Flours) ; les-
son on Kinds of Flour . '. . . . . 230
CHAPTER XLIX
CAKE
Making a Plain Cake; Frosting; class experiment (Bread
Flour and Pastry Flour) ; lesson on Cake-making . . 233
CHAPTER L
BAKING-POWDER BISCUITS
Biscuits; Sour Milk Gingerbread; lesson on Baking-powder
Biscuits . ; . . . ..... . 237
CHAPTER LI
SUGAR COOKIES
Class experiments (Yeast) ; Sugar Cookies ; Ginger Snaps ;
lesson on Yeast . . . . - * * . . . 240
CHAPTER LH
BREAD-MAKING
Mixing and Baking Bread ; class work (Kneading) ; lesson
on Bread and Bread-mixing ...... 244
XX CONTENTS
CHAPTER LIH
BREAD
PA09
Rolls; Graham and Oatmeal Bread; class work (Parker
House Rolls) ; lesson on Bread and Bread-baking . . 249
CHAPTER LTV
PIES
Class experiments (Proportions of Fat and Liquid to Flour) ;
Pie Crust ; Apple Pie ; lesson on Pastry .... 254
CHAPTER LV
DOUGHNUTS
Class experiments (Fats) ; Doughnuts ; lesson on Fats . 257
CHAPTER LVI
MILK FATS
Butter; Whipped Cream; Philadelphia Ice Cream; class ex-
periments (Cream and Butter) ; lesson on Butter . . 262
CHAPTER LVII
CUSTABDS
Custard Ice Cream ; Boiled Custard ; Baked Custard ; Frozen
Custard; lesson on Milk . . . .... 267
CHAPTER
ACIDS AND MILK
Cream of Tomato Soup ; Lemon Milk Sherbet ; class experi-
ments (Acids and Milk) ; lesson on Milk (Continued) . 272
CONTENTS Xxi
CHAPTER LIX
CUBD OF MILK
PAQB
Cottage Cheese; Junket Custard; class experiments (Effect
of Heat on Sour Milk) ; lesson on Food for Children . 276
CHAPTER LX
CHEESE
Cheese Pudding; Welsh Rabbit; class experiments (Effect
of Extreme Heat on Cheese) ; lesson on Cheese . . 281
CHAPTER LXI
SALADS
Class experiments (Emulsions) ; Salad Dressings ; lesson on
Arrangements in the Kitchen and Dining Room . . 285
CHAPTER LXII
LUNCHEON
Prepare and Serve a Luncheon ; lesson on Menu-making . 292
APPENDIX
Food Requirements ; Tables of Height and Weight ; Table
of Fuel Values . . , 7 . . . . .297
SUPPLEMENTARY LABORATORY LESSONS . . 313
INDEX 315
INTRODUCTION
PLANNING meals is often thought a very simple piece
of work, and perhaps it is comparatively so, if it is not
necessary to consider either time or money. But people
are beginning to believe that it is really their duty to
consider both, and many of us have to, whether we
would or no.
Think, then, of all that it is necessary to know in order
to do this work well. First, the housewife must know
what the income is and how it is to be divided. Only
thus can she determine what the family can afford to
spend for food.
Next, she must know, in order to decide what is to be
served for dinner, what is in the market, and a great deal
about qualities and prices. In selecting meats, it is
necessary not only to be able to tell whether a given
piece is good, but to know what cuts are appropriate for
different uses. In choosing fresh fruits and vegetables,
a knowledge of what is in season is essential for wise
buying, since out of season they may be poor and
yet command even higher prices than good ones when
these are plentiful. Some knowledge of brands of canned
and package goods is useful, but will probably have to
be acquired locally. Even with all this information, a
knowledge of the part played by these foods in nourish-
ing the body, and of their relative value from this point
xxiv INTRODUCTION
of view, should govern the actual purchases ; and, curi-
ously enough, these considerations have no connection
with the price.
It is surely necessary to know how to prepare and serve
food in an appetizing manner. At first thought a knowl-
edge of cooking might seem necessary for the planner only
when she is also the cook; but without such knowledge
how is the manager to look out for the use of left-overs,
the saving of fuel, the adjustment of plans to oven space,
and above all, the amount of work required ? One meal
which seems very much like another may involve three
times as much work in preparation, and the real cost of
food is not merely the price paid for it in the store, but
also the cost of the labor required to prepare it, and of
the fuel to cook it.
From such consideration, it is evident that the planning
of meals requires broad knowledge, and it is easy to see
why food study is taking such a prominent place in school
work, and why it involves so much more than the art of
cookery.
FOOD STUDY
FRUIT
CODDLED APPLES
APPLE SAUCE
A. Class Experiment. THE SPOILING OF FRUITS.
Put three test tubes, with corks to fit, in a pan of eold
water and heat slowly to boiling. Empty the tubes and
half fill with uncooked fruit cut in small pieces.
1. Fill up the first tube with cold water, cork, and seal
with paraffin or wax.
2. Cover fruit in the second tube with water and boil
for three minutes. Fill up with boiling water ; cork
and seal.
3. Repeat (2), but do not cork the tube.
4. Take a tube which has not been boiled. Cook a
little fruit separately and, when it is cooled, put it
into the tube. Add enough of the fruit and juice to
fill it ; cork and seal.
Note results at the end of twenty-four and forty-eight
hours, and after several days. Under which conditions
does the fruit keep ?
1
,,J ,Si .-,?*.
B. KEEPING FRUIT FROM BREAKING WHILE COOKING.
1. Pare a peach. Cook half of it in half a cu of water.
When it is tender, add two tablespoons of sugar.
2. Make a syrup of half a cup of water and two table-
spoons of sugar, and cook the other half of the peach
in it.
Compare the results.
C. Prepare coddled apples and apple sauce, using one
apple.
CODDLED APPLES.
The apple may be washed and pared, and cooked whole
or quartered and cored ; but th'e whole apple or the piece,
whichever is used, should keep its shape. Therefore cook
gently. Use one-third as much sugar as water for the
small quantity. When shall the sugar be added? A bit
of stick cinnamon may be cooked with the apple.
APPLE SAUCE.
Wash, pare, core, and cut up an apple. Use about one-
third of a cup of water to an apple, and one-third as much
sugar as water. Here the apple should not keep its shape.
When shall the sugar be added? One-half teaspoon of
lemon or nutmeg or cinnamon may be added.
FRUIT
The botanist defines fruit as the seed-bearing parts of a
plant. However, we commonly call some of the fruits
vegetables; as, for example, tomatoes, cucumbers, and
squash. Then there are a few vegetables, such as rhu-
barb, which we use and think of as fruit. Only a few years
ago it was hard to obtain fresh fruits in winter. Bananas
could be obtained only in the larger cities, and oranges
FRUIT
US Deportment of Agriculture
b Deportment or Agncutti
Office of Experiment Stations
A C.True. Director
R-epared by
C.FLANGWORTHY
Expert in Charge of Nutntwn Investigations
COMPOSITION OF FOOD MATERIALS
OfflD ^^ &%x ^^ nrrrm B /ei value
Fat Carbohydrate, A* Water
APPLE
EOBCE PORTKJM
DRIED FIG
eaei PORTION
COMPOSITION OP FRUITS
4 FOOD STUDY
and lemons were very expensive. Now conditions have
changed. Transportation is so much more rapid that with
the development of refrigeration we can have fruit
shipped from a distance and so are enabled to have fresh
fruit all the year round.
Fruit is sometimes classified from a nutritive standpoint,
as flavor fruit and food fruit. Some fruit contains so much
water that there is comparatively little nourishment to be
had from it. Watermelons and strawberries, for exam-
ple, contain more than ninety per cent water. But
nearly all fruit has real food value. Many of the fruits
which we think of as flavor fruits contain considerable
nutrition. A large-sized orange will furnish as much
nourishment as an egg, or as a banana, or as two
apples, mainly on account of the large amount of sugar
present.
The flavor of different fruits is due to sugars, acids,
and "ethereal" bodies. These ethereal bodies, or volatile
oils, as they are called, are present in such small quantities
that they are sometimes impossible to detect chemically,
but it is undoubtedly due to their presence that different
fruits have distinctive flavors. The acids present are
known as organic acids. In fruits these are such acids as
malic, tartaric, and citric. Some of these are burned in
the body, just as other food is, and form carbon dioxide
and water. They do not have to be excreted as do the
mineral acids, and so, in the body, we need hardly con-
sider them as acids at all.
The salts which are present in fruits are valuable. We
count the fruits, then, as foods which furnish alkaline
elements, and these help in keeping the blood in proper
condition.
Dried fruits are, of course, more nutritious, pound for
pound, than fresh fruits. A pound of fresh fruit will give
FRUIT 5
about six ounces when dried. A pound of dried fruit, then,
will be nearly three times as nutritious as a pound of fresh
fruit. We must take facts like these into account when
we consider whether dried or fresh fruit is more expensive.
We pay more for a pound of raisins than for a pound of
grapes, but since the raisins contain so much less water we
really are paying less for the amount of food material to be
obtained from them.
Fruits are particularly desirable in the diet because of
their flavor. They may increase greatly the palatability
of an otherwise somewhat tasteless meal. Jam on our
bread appeals to all of us. This increased palatability
probably means increased digestibility, so that, for this
reason alone, we should feel justified in including fruit
in the diet. However, the salts and acids present are
so important that we need fruits for this reason also,
even if their palatability does not tempt us. The salts
and acids in some fruits have a laxative effect. Prunes
and figs are examples of this class. Blackberries and
peaches are not laxative. Most other fruits rank be-
tween these two groups.
The amount of fiber present in fruits is small compared
with the amount in vegetables, but there is enough to
make some varieties distinctly more easily digestible if
cooked. Cooking softens the fruit. Fruit is also cooked
to preserve it. Cooked, dried, and preserved fruits have
all the advantages in the diet of fresh fruits.
Among the fruits considered the most digestible are
grapes, oranges, lemons, cooked apples, figs, peaches,
strawberries, and raspberries. Some people, however,
cannot eat strawberries. Only a little less digestible are
raw apples, prunes, pears, apricots, bananas, and fresh
currants. Bananas contain a good deal of starch if they
are unripe, and so in this condition are not very digestible
6 FOOD STUDY
unless cooked. When they are kept until the skins are
dark, the starch is largely changed into sugar and the fruit
is more digestible. The " strings", sometimes left on the
banana when it is peeled, are indigestible. As a whole,
fruits are digestible, although some people have idiosyn-
crasies which make a particular fruit disagree with them.
Over-ripe or green fruit is, of course, harmful.
Since much of our fruit is eaten raw, fruit should be
kept as clean as possible while it is marketed. All fruits
should be washed before being eaten, even fruits like
bananas and oranges, the skins of which we do not eat,
because we are apt to handle first the skin and then the
fruit. Such fruits as apples and oranges may be washed
and rubbed with a cloth to clean them. Fruits that have
sticky surfaces, especially if these have dried, are harder to
clean and need to be washed in two or three waters. It
is better to select packages of dates or figs which are pro-
tected from the dust, even if they cost slightly more, than
to buy those that are exposed to dirt and flies.
Fruit, then, should not be considered merely as a
luxury ; and some fruit should be included in every diet.
If it is necessary to count the pennies, choose the cheaper
varieties, which, fortunately, are as good for us as the more
expensive.
REFERENCES
U. S. Dept. of Agriculture. Farmers' Bulletin No. 293. "Use of
Fruit as Food."
Year Book U. S. Dept. of Agriculture, Separate 610. "Raisins,
Figs, and Other Dried Fruits and Their Use."
QUESTIONS
1. What is the value of fruit as food ?
2. Are these values retained in coeked and preserved fruits?
3. Why is it better to use a silver knife in preparing fruit?
CANNING FRUIT 7
4. Make a list of dried fruits in common use and their cost per
pound.
5. Make a list of the common fresh fruits, giving then* seasons and
usual cost when in season.
II
CANNING FRUIT
CANNED PEACHES
A. Class Experiment. ONE CAUSE OF FRUIT SPOILING.
Take a piece of bread, moisten it with water, and leave
it exposed upon a plate during the lesson. Then cover
with a saucer ; leave for two days. If possible, examine
under a miscroscope.
B. To CAN A JAR OF PEACHES.
In canning fruit, use a fourth to a third of the weight of
the fruit in sugar and from two and a half to three cups of
water for each pound of sugar. Make a syrup by boiling
the sugar and water together for three to five minutes.
Scald the peaches by dipping in boiling water long enough
to loosen the skin; peel, cut in halves, and remove the
stones. Then, cook the fruit in the syrup. Often, only
part of the fruit is cooked at a time, so that there need not
be an excess of the syrup. While the peaches are cooking,
sterilize a jar and cover, as the test tubes were sterilized
in the last lesson. When the peaches are done, place the
jar either in hot water or on a cloth wrung out of hot water.
Fill the jar with fruit and pour in syrup until it overflows.
If there is not enough syrup, add boiling water. As
quickly as possible, put on a rubber and screw on the
cover. When the jar is cold, screw the cover as tight as
possible, being sure that it is air tight.
8 FOOD STUDY
C. ANOTHER METHOD OF CANNING.
Fill a jar with peaches, cut in half and stoned, within
one inch of the top. Make a syrup and pour over the
fruit. Adjust the rubber, screw cover on lightly or adjust
top without clamping, and place the jar in a moderate
oven or in a steamer. Cook till the fruit appears clear and
waxy. Then remove from the oven and tighten the cover.
Compare the advantages and disadvantages of these two
methods of canning.
MOLDS
(ONE CAUSE OF THE SPOILING OF FOOD)
Molds are so well known to everyone that it is surprising
to learn that there is no such botanical classification. All
plants that do not contain chlorophyll, the coloring matter
which makes an ordinary plant green, are called colorless
plants or fungi. The fungi include mushrooms and toad-
stools, but of more interest to the housekeeper are molds,
yeasts, and bacteria. All these are plants which feed on
organic food and so may be found living on any of our
foods that are not properly taken care of.
While nearly everyone recognizes molds at sight, few
have looked at them closely enough to realize what really
beautiful plants they are. When they begin growing,
they appear at first as soft, fluffy masses which are made
up of a tangle of much-branched threads. Each thread,
called a mycelium, looks white as it is seen ordinarily $ .
but appears nearly colorless under a microscope. When
the mold is older, perhaps after two days, it may show a
color, blue, green, brown, black, red, or pink, each color
marking a different variety of mold. The color is due to
the so-called spores, which are reproductive bodies and
which, if they contained nutritive material, would be seeds.
MOLDS
9
Each different species of mold has a different way of form-
ing spores.
Perhaps the most common household mold, one that is
almost always found on moldy bread, is penicillium. This
is a blue mold ; that is, at the time of spore formation, it
becomes blue, or
bluish-green. This
color is due to the
color of the spores
themselves. When
the mold is a day
or two old, the my-
celium sends up ver-
tical threads which
soon divide into
many little
branches. Then,
each branch begins
to divide by ring-
like constrictions as
if it were trying to
make beads of itself,
until, finally, the
branch is nothing
more than a string
of little round balls,
each of which is a
spore. These spores
are so light that a breath of wind blows them away,
and they float off in the air in search of new food
material.
Mucor, another mold commonly found on bread, is
coarser than penicillium, so that the threads are seen more
easily. When it is ready to form spores, the vertical
From Conn's " Bacteria, Yeasta,
and Molds In the Home."
PENICILLIUM, COMMON MOLD, AS SEEN
UNDER THE MlCEOSCOPE
10
FOOD STUDY
threads, instead of branching, form on their ends small
round knobs or sacs, and inside these balls are formed
thousands of spores, which, when the sac bursts, are sown
broadcast. These knobs on the mold look like small
black specks. Another mold, aspergillus, instead of form-
ing the spores inside the sac, forms them as beads on the
outside.
During the process of
growth, all these molds
may send their branch-
ing threads deep down
into the food on which
they are growing so that
more than the surface
Spores in an
older colony
From Conn's " Bacteria, Yeaats, and Molds In the Home."
SPORES OP PENICILLIUM
SPROUTING
GROWTH FROM Two SPORES,
Two DAYS LATER
may be affected. As a result of their .growth, they soon
change not only the appearance of the food, but the flavor
and odor as well. If the mold is allowed to go on growing,
the food may be entirely spoiled. On the other hand, some
molds produce delicious flavors, and many of the distinc-
tive flavors of our different cheeses are produced in this
way. Fruits are particularly subject to decay as a result
of mold action. If the skin of fruit is broken, the molds
MOLDS
11
have an especially good chance to get at the food material
inside and begin the process of decay.
A tempera-
ture as hot as
boiling, or even
a little lower,
will soon kill a
plant, and
molds are no ex-
ception to this
rule. When
fruit is canned,
then, it is boiled
not so much to
rnnk thp fruit From Conn's " Bacteria, Yeasts, and Molds in the Home."
MUCOR, ANOTHER MOLD FOUND ON BREAD
as to be sure
that it contains no live spores; and then it must be
put away air tight so that no new spores can blow in.
Spores
. $ V 'J- '.'
From Conn's " Bacteria, Yeasts, and Molds In the Home."
ASPERGILLUS, SHOWING MYCELIUM AND SPORE CLUSTERS
12 FOOD STUDY
This is one of the things accomplished in canning, al-
though the plants to be guarded against may be bacteria
and yeasts as well as molds.
REFERENCES
CONN. "Bacteria, Yeasts, and Molds in the Home." Section I,
Molds.
Cornell Reading Course for the Farm Home. "The Preservation of
Food in the Home," Part I.
U. S. Farmers' Bulletin No. 426. "Canning Peaches on the Farm."
U. S. Farmers' Bulletin No. 359. "Canning Vegetables in the
Home."
U. S. Farmers' Bulletin No. 203. "Canned Fruits, Preserves, and
Jellies."
Ohio State University Extension Bulletin, Vol. VI, Supplement 2,
No. 2. "The Canning of Fruits and Vegetables."
QUESTIONS
1. After sterilizing, why must the fruit be kept covered and air
tight?
2. After a jar is sterilized why should it not be wiped out with the
dish cloth ? Why must care be taken not to touch the inside of the
jar with the fingers?
3. Why is the rubber dipped in boiling water, and why is it not
boiled with the jar and cover ?
4. How can the jar be tested before using ? If leakage is due to a
poorly made jar and not to a poor rubber, what uses may be made of
the jar ?
5. Describe the different methods of canning.
6. How can a jar that sticks be opened ?
7. What different styles of cans are commonly used ? Discuss the
advantages of each kind.
JELLY 13
III
JELLY
APPLE AND GRAPE JELLY
A. TRIAL JELLY.
Place in saucepans one-half cup of crab apples and one-
half cup of pears or peaches, cutting them into pieces.
Just cover with water, later adding more if necessary.
Cover and boil, until fruit is soft and will mash easily.
Make a jelly bag out of double cheesecloth by folding and
sewing it in the shape of a cornucopia; and, when the
fruit is done, allow it to drip through the bag, at first
without squeezing. Examine juice, then squeeze the
remainder through and note the difference.
1 . Place in glass cups one teaspoon of each juice obtained,
and add an equal amount of alcohol. Let it stand
five minutes. Observe the pectin, the substance
which furnishes the thickening for jelly. Compare
the amounts found.
2. Now try to make jelly out of the rest of the two ex-
tracts by adding to each an amount of sugar equal to
three-fourths of the amount of the juice, and boiling
until it is determined whether the mixture will "jell."
Tests for jellying :
Place a few drops of jelly on a cold plate and put in a
cold place. When it is done the drops should harden over
the surface and wrinkle when scraped with a knife or
spoon. While making the test, remove the jelly from stove
to prevent over-cooking.
Perhaps the best, because the quickest, test is to allow
a little of the juice to drop from the spoon. When the
mixture is done, these drops should jelly and break off.
14
FOOD STUDY
US Department of Agriculture
Offie. of Etpermnt Stabm
AC True. Doctor
R-epored by
CFLANGWORTHY
fcpert n Charge of Nutrition Investigations
COMPOSITION OF FOOD MATERIALS
nilill 883 KEgaa K^?3 Illlllll BSBB Fuel Vqlue
W.
GRAPE JUICE
UNfERMENTED
CANNED
FRUIT
Water: 77 2
COMPOSITION OP FRUITS AND FRUIT PRODUCTS
PRINCIPLES OF JELLY-MAKING 15
B. To MAKE JELLY.
Make grape jelly, using one cup of material. The
grapes should be picked over and washed before being put
into the saucepan. It is not necessary to add more water.
After the sugar is added to the juice, remove any scum that
forms. Sterilize the jelly glasses before filling. When
the jelly has hardened, cover with melted paraffin.
PRINCIPLES OF JELLY-MAKING
Because fruit juices differ so much in their composition,
it is impossible to give general directions sufficiently exact
always to insure a perfect jelly. In fact, perfect jelly is
rather seldom made. To be ideal it should not only be
beautifully colored and transparent, but so tender that it
cuts easily, and firm enough to keep its shape, but not so
firm that it does not quiver.
In order to make jelly, fruit juices must contain two
substances, acid and pectin, and these should be present in
proper proportion. When fruit is cooked, pectin is formed
by the action of water and heat on a substance called
pectose which is present in the raw fruit. This pectose is
closely related to cellulose 1 and probably is closely asso-
ciated with it in the cell walls of the fruit. It is absolutely
unlike cellulose, however, in its property of being affected
by boiling water. The pectin which is obtained from the
pectose is the substance which gives texture to our jellies.
It is possible to make jelly by great concentration without
the addition of any sugar at all to the fruit juice, but the
jelly that is formed is tough and gummy and not palatable,
as well as being much less in amount than is produced
ordinarily. The addition of sugar in the presence of the
1 Cellulose is the chief substance of which the cell-walls of
plants are composed.
16 FOOD STUDY
right amount of acid seems to precipitate the pectin and
make the jelly set.
Not only does one fruit differ from another in the amount
of these two substances which it contains, but different
lots of the same kind of fruit may differ materially. As
fruit ripens it contains less acid, and less pectin as well,
and over-ripe fruit may fail to jelly at all. Fruit that is
not fully ripe is much safer to use than that which is over-
ripe. Some fruits contain too much acid, unless they are
diluted with water, but it is quite possible to add so much
water that there is neither enough pectin nor enough acid
present. As a rule, very juicy fruits need have only
sufficient water added to prevent burning. When they
are soft enough to mash easily, the whole is transferred
to a cheesecloth bag wrung out of hot water, and the juice
is allowed to drip through. If the pulp is squeezed, the
resulting juice is not so clear, but the flavor is not changed.
Less juicy fruits must be covered with water while they
are cooked. The alcohol test for pectin may be relied
upon to tell whether the proper concentration is obtained.
The amount of sugar used, like the water, varies with
the kind of fruit. It is better to err on the side of
using too little, rather than too much. Jelly made from
currants and grapes that are rather green may have as
much as one part of sugar to one part of juice, but, in
general, three-quarters of the amount of the juice is the
right proportion of sugar. If at any time the alcohol test
does not show plenty of pectin, lessen the amount of sugar.
Too much sugar not only will give a jelly which is very
sweet, but may give one that is syrupy. The amount of
acidity can, perhaps, be as well judged by taste as in any
other way. Before the sugar is added, the fruit juice
should be distinctly tart.
Jelly can be made from fruits that are lacking in acid
PRINCIPLES OF JELLY-MAKING 17
by the addition of some acid of vegetable origin, such as
tartaric or citric. This does not always improve the
flavor. The acid is commonly added by stewing with
such fruits some other fruit which will supply the lack-
ing acid.
Most housekeepers do not realize that if fruit is allowed
to drip and is not squeezed through the jelly bag, the pulp
may be returned to the kettle and boiled with more water, f
which gives additional extractions. The last should be
concentrated until the alcohol test shows the right pro-
portion of pectin. The first extract is usually made into;
jelly by itself, because it has the finest flavor, while the,
subsequent extractions are worked up together. Some-\
times even a fifth extraction, if it contains sufficient i
pectin to make it worth while, can be made.
The time necessary for making jelly differs with differ-
ent fruits, with the amounts of pectin and acid present,
and with the proportion of sugar used. The jelly, however,
should be made as quickly as possible. If the fruit is
allowed to simmer, too long heating of the pectin with the
acid may entirely destroy this substance. For this reason
the sugar is heated before it is added to the juice; if it
cools off the mixture, the whole must be cooked a longer
time.
There are three ways of making jelly. In one, the
sugar is added at once to the fruit juice ; in another, the
fruit juice is boiled for some time before the sugar is put in ;
while in the third, it is put in when the fruit juice has
cooked about half the total time necessary for making the
jelly. Probably the third of these methods is the best.
After the jelly has hardened, it maybe covered in the old-
fashioned way by cutting a piece of paper which will just
fit into the top of the jelly glass, and dipping it into alco-
hol or brandy, placing this directly on the jelly, and then
18 FOOD STUDY
covering the top of the glass with another piece of paper
large enough to tie or paste down. The alcohol is used to
prevent the growth of molds, spores of which may have
settled on the surface while the jelly was cooling and form-
ing. The outer piece of paper is used to prevent the access
of fresh spores and to lessen evaporation. A somewhat
easier method is to pour a layer of melted paraffin over the
top of the jelly. The paraffin should be hot, so as to kill
any germs which may be present. If, in cooling, the
paraffin shrinks from the side, leaving a crack between it
and the glass, more paraffin should be poured in.
Jelly keeps best in a cool, dry place. Since the color
of fruit sometimes fades, it is well to keep jellies and fruits
where they are not exposed to too much light.
REFERENCES
Cornell Reading Course for the Farm Home. Vol. 1, No. 15.
"Principles of Jelly-Making."
U. S. Farmers' Bulletin No. 203. "Canned Fruits, Preserves,
and Jellies."
U. S. Farmers' Bulletin No. 388. "Jelly and Jelly Making."
QUESTIONS
1. Why should not saucepans or spoons made of aluminum, or tin,
be used in cooking fruit ?
2. Why should jelly bags be dipped into hot water before being
used?
3. Why are jelly glasses put in hot water, or on a cloth wet in hot
water before filling ?
4. Why, in jelly-making, is fruit not quite ripe preferred to fruit
over-ripe ?
5. Why is jelly covered after making ?
6. Where is it best to store jelly for keeping ?
7. Make a list of fruits which are good for jelly-making and star
those that are so juicy as to require no water added in the making.
JELLY-MAKING 19
8. Make a list of combinations of fruits that would make good
jelly.
9. Compare the cost of the canned fruit and jelly made in the
laboratory or at home with that of the commercial products.
IV
JELLY-MAKING (continued)
A. REPEATED EXTRACTIONS OF JUICE FOR JELLY-
MAKING.
Use sour apples or quinces.
1. Cut fruit in small pieces, without peeling or removing
seeds. Place one cup of fruit in a kettle, cover with
water, and cook until the fruit can be mashed easily.
Strain juice through a jelly bag, allowing it to drip
through without squeezing the bag. Reserve the
pulp for a second extraction. Test one teaspoon of
the juice for pectin. Keep the juice for jelly-making,
marking it "Extraction 1."
2. Add water to the pulp reserved in (1) and proceed as
before. Test one teaspoon of the juice for pectin.
Reserve the rest of the juice, Extraction II, for jelly-
making.
3. Make a third extraction. Again test one teaspoon
for pectin. Reserve this third extraction for jelly-
making.
B. JELLY FROM THESE EXTRACTIONS.
1. Make jelly from Extraction I, using :
a. Three-fourths as much sugar as juice.
b. Equal parts of sugar and juice.
20 FOOD STUDY
2. Boil Extractions II and III together rapidly, until the
resulting juice approximates the richness of Ex-
traction I. (This may be tested by alcohol, by the
color and taste.) Measure. Make jelly, using pro-
portion of sugar to juice that is found to give the
best results.
C. Class Experiments. FOOD PKESERVATIVES.
Sterilize small bottles or test tubes.
1. Place a piece of uncooked fruit in each.
a. Cover fruit with brine.
6. Cover fruit with a fifty per cent solution of sugar.
c. Cover fruit with a ten per cent solution of sugar.
d. Cover fruit with water and add ground cinna-
mon, clove, or mustard.
e. Cover fruit with water and add allspice or
nutmeg.
/. Cover fruit with vinegar.
g. Cover fruit with oil.
h. Cover fruit with alcohol.
2. Allow the tubes to stand for several days and ex-
amine from time to time until it is determined which
substances act as preservatives.
D. Class Work. PREPARE CUCUMBER PICKLES.
Make unripe cucumber pickles, using one-fourth of a
cup of cucumbers.
Wipe about a dozen small, unripe cucumbers and cover
them with brine made by dissolving one tablespoon of salt
to a cup of boiling water. After three days, drain off the
brine, reheat it to boiling, and again pour it over the
pickles. After a second three days, drain the cucumbers,
cover them with boiling water in which a salt spoon of alum
has been dissolved for every cup of water used. Allow
them to stand for six hours, then remove them from the
YEASTS AND BACTERIA 21
alum water, and cook for ten minutes in a part of the fol-
lowing mixture heated to boiling :
1 pint vinegar f tbsp. allspice berries
| red pepper | tbsp. whole cloves
Pack the cooked pickles in a jar and strain the rest of the
mixture over them.
YEASTS AND BACTERIA
As has already been said, yeasts as well as molds belong
to the colorless plants and fungi. The yeast which is
used in making bread is a collection of thousands of tiny
yeast plants, each of which is too small to be seen without
the aid of a microscope. These plants are even less like
ordinary plants than are the molds ; they consist merely
of a single cell which appears, under the microscope, as a
colorless oval. These yeast plants are so small and light
that, like the spores of the molds, they float about in the air.
Fruits preserved in sugar are especially apt to undergo a
change which, as can be seen at once, is not due to mold
growth. This is the action that takes place when preserves
" work " or ferment, and it may occur also in jellies or syrups.
Anything which contains sugar and water may show this
change. The change is characterized by a sharp, pungent
taste, and at some stages by the formation of bubbles
through the liquid. Whenever these phenomena occur,
it is a sign that growing yeasts are present. For yeasts,
when they grow, are able to break up the sugar which is
present and change it partly into alcohol, which gives the
stinging taste, and partly into a gas called carbon dioxide,
the escape of which through the liquid makes the bubbles.
While yeasts are producing these results, they are mul-
tiplying rapidly by a method called budding. In this
22 FOOD STUDY
way new cells are formed which appear first as very tiny
buds on the sides of the first cells and gradually grow larger
and larger until finally they separate into independent
cells. When active fermentation is going on, the yeast
present is always found to be in this growing state. If,
however, conditions are unfavorable, some yeast plants
can form within each cell a number of spores, each of
which is capable of developing again into a new plant.
This spore formation usually happens if there is sufficient
moisture present, but not enough food to produce growth.
The air may be laden with these spores and even with
some of the yeast cells themselves, as well as with the
spores of molds.
Other micro-organisms carried by the air are called
bacteria. They are as simple in structure as the yeasts,
and like them consist of single cells. They may, however,
have three distinct shapes. Some are like little rods and
are called bacilli (a bacillus, for a single one), others are
like spheres and are called cocci, the third variety is spiral
and is named spirilla (in the singular, spirillum). But
all these, no matter what shape they may be, reproduce
in the same way, and it is this method of reproduction
which distinguishes them from the yeasts. Each cell
grows a little longer than it was before and then breaks in
two, each half being an individual. This process, known
as reproduction by fission, gives to bacteria the name of
fission fungi.
Like yeasts, some bacteria can produce spores under
unfavorable conditions. A bacterium, however, instead of
producing a number of spores, forms only a single one.
The advantage of the spore state seems to be in the greater
power of resistance that the spore possesses it is less
easily killed by heat or cold or drying. If food is being
sterilized and spore-forming bacteria are present, it is quite
YEASTS AND BACTERIA 23
possible that the heating will kill all of the bacteria but the
spores will be left alive. By the following day, however,
the majority of these spores will have again changed them-
selves into the ordinary forms of bacteria, and a second
heating will kill these forms. A third heating is safest to
make sure that any spores remaining the second day are
destroyed. Both yeasts and bacteria are too small to be
seen without a microscope ; but of the two, yeasts are much
the larger. While a yeast cell is about one three-thou-
sandth of an inch in diameter, even the largest bacterium
has a diameter of not more than one ten-thousandth of
an inch. It might well seem as if organisms as small as
this could not do us either much harm or much good, and
this would probably be true if it were not for the wonderful
rate at which they can multiply. In a bacterium, division
may take place every half hour, and at that rate, in only
one day, conditions being favorable, a single cell could
produce about seventeen million others. If, then, food is
to be kept from spoiling, it is obviously necessary to
exclude the entrance of even one bacterium.
When bacteria first act upon food, the result may be
only beneficial; the good flavor of butter and some
cheeses is undoubtedly due to their action. Bacteria,
however, will finally render food unfit for use, producing
decay and putrefaction. But what a world it would be
if micro-organisms did not bring about these processes.
Our world would be littered with useless material, and the
soil long ago would have become exhausted.
Bacteria may be divided into three distinct classes :
first, those capable of producing diseases, such as typhoid
and diphtheria; second, those which in the process of
growth produce substances poisonous to us. These sub-
stances, called ptomains, are the cause of the ptomain poi-
soning cases which occur from time to time. The third
24 FOOD STUDY
class is composed of those that are either harmless or
beneficial to us. The bacteria which cause milk to sour not
only are not any more poisonous to us than are any of the
other vegetable plants used for food, but they may be of
positive benefit in keeping down the growth of more harm-
ful organisms.
"Swat the fly" has become a slogan in modern times.
A glance at the enlarged diagram of a fly, particularly of
the feet, will show why it is considered objectionable to
have flies around, and especially so to have them crawl
over food. Coming from infected material and filth, they
may bring with them all kinds of germs. If the germs are
introduced into food material, where every condition is
right for their reproduction, it is evident how trouble
may occur. It is very necessary then, that flies be ex-
cluded from houses as far as possible. Any flies that find
entrance must be killed or caught, and care must be taken
not to allow heaps of manure or garbage, or other fly-
breeding material, to stand long enough for their larvas to
develop and escape. Much the easiest method of keeping
free from flies is to control possible breeding places. A
new kind of garbage can acts as fly-catcher and, placed
just outside the house, may catch many flies which would
otherwise find their way in. Then garbage and flies
together must be disposed of. Other insects may, of
course, also act as carriers of germs, but the fly especially
brings them.
REFERENCE
CONN. " Bacteria, Yeasts, and Molds in the Home ", sections on
Bacteria and Yeasts.
QUESTIONS
1. Give instances in which bacteria are beneficial.
2. Why may there be more spores on the fruits and vegetables
SWEET PICKLED PEACHES 25
giowing in a very dry season ? Why would such fruits be harder to
can successfully ?
3. Why, in making cucumber pickles, is the brine reheated at
intervals ?
4. How should garbage cans be cared for ?
5. What are the best means of disposing of garbage ?
6. Why should all foods and dishes be covered carefully when
sweeping or dusting is going on ?
SWEET PICKLED PEACHES
A. PREPARE SWEET PICKLED PEACHES.
Use one peach.
5 peck peaches 1 pint vinegar
2 Ibs. brown sugar 1 oz. stick cinnamon
Cloves
Scald the peaches, peel them, and stick them with three
or four cloves. Cook until tender a few of them at a time,
in a syrup made by boiling together the sugar, cinnamon,
and vinegar. Put in jars.
B. Class Experiment.
CONDITIONS FAVORING GROWTH OF MICRO-ORGANISMS.
Try the following experiments, using petri dishes,
or saucers covered with tumblers or sheets of glass :
1. Place a piece of bread in each of two dishes.
Leave the first piece of bread dry; moisten the
second piece with water. Expose both to the air
for five minutes in a room where people are moving
about. Cover, and keep both in a dark place (as,
for example, in a cupboard) for two days, and ob-
serve the results.
26 FOOD STUDY
2. Place a piece of bread in another dish and moisten
it. Expose it for five minutes in a room when no
one but yourself is present, and do not move more
than you can help during the exposure. Keep this
dish also in the dark for two days and compare with
the second dish in (1).
3. Put pieces of bread (moistened) in four dishes, and
expose all at once for five minutes in a room with
people moving about.
a. Keep the first in a warm room.
b. Keep the second in an ice-box.
c. Keep the third in the sunlight as much as possible.
d. Keep the fourth in a dark, warm place.
Examine these at the end of two days. If necessary,
let them stand longer. What effect has dryness or
moisture, warmth or cold, light or darkness, on the
growth of mold ? Account for the difference in (2).
CONDITIONS FAVORABLE TO THE GROWTH OF
MICRO-ORGANISMS
Food might seem to be the first condition necessary to
the growth of micro-organisms, and so it is ; and yet they
seem able to live for a fair length of time without food.
They blow around in the air, or are transmitted by water,
in neither of which elements are they fed. Under these
circumstances, it is true, they are not growing or multiply-
ing, and may even be in the spore state, but once the
organisms reach available food, they begin to grow and
reproduce with wonderful rapidity.
Water, as well as food, is necessary, but different
organisms vary somewhat in regard to the necessary
amounts. Bacteria and yeasts require a goodly propor-
GROWTH OF MICRO-ORGANISMS 27
tion of water, and it is only in watery foods that they are
capable of much growth. Sugar and flour, for example,
are much too dry for them. Twenty-five to thirty per
cent of water is necessary for any growth, and, even then,
it will not be vigorous. Most bacteria cannot grow in
foods which are strongly acid, but molds do not mind
the acid, and as only small percentages of moisture are
necessary to keep them alive, in damp weather as dry a
food as flour may become moldy. Even books and clothes
may mold in a damp room. Mildew is one species of mold.
Bread that is in a closed bread-box is apt to become
moldy if left too long ; but if bread is spread out, exposed
to the air, it will probably dry without any molding at all.
Possibly this is because a moving current of air dries up
the moisture ; but, whatever the reason, it is true that mold
grows best in still air.
Bacteria differ greatly in relation to air. Some grow
only in the presence, others in the absence of it, and some
can prosper either way. The bacteria that live without air
cause putrefaction and are perhaps most likely to produce
ptomains; but the majority of bacteria grow best in an
abundance of air, and most foods begin to spoil on the
surface.
Direct sunlight rapidly kills bacteria, and any daylight
makes them grow more slowly and less vigorously. Molds
may grow in either light or darkness, but they, too, grow
best in a dark place. Plenty of light and fresh air, then,
are the housekeeper's allies in the fight against micro-
organisms.
Another method of checking the growth of micro-
organisms is by means of low temperatures. Few organ-
isms can make any but the most feeble growth in the cold.
Even rather slight differences in temperature seem to have
surprisingly great effects.
28 FOOD STUDY
For this reason food is placed in an ice-box to delay the
growth of the micro-organisms, but as the temperature,
even in very well-constructed refrigerators with a large
ice chamber, is forty to forty-five degrees, usually nearer
fifty degrees Fahrenheit, growth can be delayed only for
a limited time. Such food will spoil eventually. But a
temperature even of sixty degrees is still a great aid in
keeping food temporarily. Cold storage is more efficient
than home refrigeration, because a lower temperature is
used.
There are other means of preserving food, besides the
use of cold temperatures. Drying evidently prevents the
growth of bacteria, since they need so much water, and,
if this is thorough, it may also prevent mold action.
Dried fruits of all kinds have long been used, as have
also some dried vegetables. Lately, more kinds of dried
vegetables have been put upon the market, and even
desiccated soups. All these are good food, as nutritious
as before drying, but they do not retain quite the
original flavors.
Foods which can be boiled and canned may be made
truly sterile, and if the process is carried out properly, such
materials will keep indefinitely. Fruits and vegetables
may well be taken care of in this manner.
In recent years, still another method of preserving food
has been used. This consists in the addition of something
which will at least lessen the growth of germs, if not en-
tirely prevent it. The difficulty is to find substances which
will do this and yet have no harmful effect upon the people
who eat the food. Among the substances commonly
used for this purpose are borax, benzoic and salicylic
acids, and formalin. These are all known to be harmful if
taken in large amounts, but they are believed to have com-
paratively little effect in small quantities. But because, if
FOOD PRESERVATIVES 29
they are allowed at all, it is difficult to be sure that they
will be in sufficiently small amounts, and because repeated
doses possibly may cause trouble, or small doses from a
number of foods combine to make a large dose, and because
some people (such as young children and invalids) are
more susceptible to them than others, the national pure
food law has forbidden the ordinary use of them, unless
the kind and amount of any such added substance is
plainly printed on the bottle or can in which the food is
sold.
There are, however, some food substances which, them-
selves, have something of the preserving effect. Mixing
foods with sufficient sugar protects them well from bacteria
or mold growth, but not quite so well against yeasts.
Raisins, dates, and figs all have so much sugar in them that
it is not necessary to add any more to insure their keeping
well, when they are partially dried. Salt, too, has preserv-
ative action, and salting fish is a usual device for keeping
it. Other foods, like corned beef, are kept immersed in
brine, that is, in salt and water. Salted butter, too,
keeps better than fresh, and perhaps that is why so little
fresh butter is used in this country. Salty foods are un-
doubtedly not so digestible as fresh, and the use of such
foods for invalids and young children is questionable.
Vinegar, sometimes reinforced by spices, is another food
preservative, but pickled foods will not keep indefinitely.
Many of the common spices also have some preservative
power. Mince meat, if kept cool, will remain in good
condition for a long period. Fruit-cake, which is highly
spiced, keeps well. Sausage is another food which is
spiced in order to prevent spoiling. But pickled or spiced
food, like that preserved in salt, is probably far less digest-
ible than in the original form, and the too frequent use of
it is to be avoided.
30 FOOD STUDY
REFERENCES
U. S. Dept. of Agriculture. Farmers' Bulletin No. 375. "Care of
Food in the Home."
Farmers' Bulletin No. 459. "House Flies."
Farmers' Bulletin No. 353. "The Ice-Box."
CONN. "Bacteria, Yeasts, and Molds in the Home", sections on
Yeasts and Bacteria.
Cornell Reading Course for the Farm Home . ' ' Preservation of Food
in the Home ", especially pages 281-286 inclusive.
QUESTIONS
1. Under what circumstances is it wise for a housewife to put up
much fruit ?
2. Why is drying a means of preserving fruits and vegetables ?
3. What preservative is sometimes added to commercial catsup?
4. How must an ice-box be taken care of ?
5. What foods should never be placed in an ice-box?
6. What kinds of foods is it unnecessary to keep in a cool place,
and why ?
7. Why should butter and milk be covered when in the refrigerator,
and if possible kept in a compartment by themselves ?
8. When a bread-box smells musty how must it be cared for ?
VI
USE OF WATER IN COOKING
BOILED POTATOES
MASHED POTATOES
A. VARIOUS METHODS OF BOILING POTATOES.
(Each student is to try one way and compare the result
with the others.)
1. Wash and scrub a potato. Cook it in boiling salted
water until it is soft. Allow one teaspoon of salt to
one quart of water.
USE OF WATER IN COOKING 31
2. Boil a potato as directed in (1), but pare it before
boiling.
3. Boil a potato as in (1), but, before boiling, cut off a
strip of the skin all around the potato.
How do these potatoes differ in color and in mealiness,
after they are done ?
Mash the potato with a fork. Beat till light and
creamy. Add two teaspoons of hot milk, one-half
teaspoon of butter, and season with salt, while beat-
ing. Heap the potato on a buttered plate and make
an indentation in the middle of the heap. Open an
egg, being careful not to break the yolk, slip it into the
indentation in the potato, and place all in an oven
until the egg is cooked sufficiently to suit taste.
Season egg with a very little butter, salt, and pepper.
Pimento may be rubbed through a strainer and
beaten into the potato at the beginning to add color
and flavor.
B. Class Experiment. COMPOSITION OF A POTATO.
(To be carried out while the potatoes are boiling.)
1. Pare a small potato; cut off a slice and leave it
exposed to the air for half an hour.
2. Grate the rest of the potato into a piece of cheese-
cloth. Gather up the corners of the cloth and, by
squeezing, press out all the liquid possible. Then
wash in a bowl of water till nothing more can be
extracted. Allow the water to stand, and examine
the sediment. Look at it under the microscope.
Boil a portion of it. Test a portion with iodine. A
blue color indicates the presence of starch.
3. Examine the contents of the cheesecloth. What
ingredients of potato have you found so far ?
4. Put a pared potato into a large kettle of cold water,
32 FOOD STUDY
and then put the kettle on to boil. When the
potato is cooked, compare it with those started in
boiling water in (A).
C. Class Experiment.
DIFFERENT STAGES IN THE BOILING OF WATER.
Heat some water in a saucepan to boiling ; meanwhile,
with a thermometer, take the temperature of the water
at the following stages :
1. When the first small bubbles appear on the bottom
and sides of the pan. (What are these bubbles ?)
2. When the water feels neither hot nor cold to the hand.
(Lukewarm)
3. When somewhat larger bubbles appear around the
edge and at the bottom of the pan. (Scalding)
What are these bubbles ?
4. When the bubbles begin to rise. (Simmering)
5. When the bubbles rise rapidly, breaking, and com-
pletely agitating the surface of the water. (Boiling)
6. Increase the heat and see if the water gets hotter.
POTATOES
The name potato is a corruption of the last part of the
Latin name for sweet potatoes, ipomcea batata, but the
name by common consent is given to our white potato.
White potatoes are a native of America, perhaps of Chile,
and were not known in Europe until about 1580. They
were introduced into North America about the same
time. At first, they did not meet with great favor in
Europe, and it was not until there was shortage in a series
of staple crops that they sprang into favor. Now they
have been adopted in Ireland to such an extent that they
form a large part of the food of the people, and for that
reason are often called Irish potatoes.
POTATOES
33
Potatoes form forty per cent of the total vegetable crop
of the world, so that their name of king of vegetables is not
undeserved, and they are next in importance among the
vegetable products to cereals. When we compare these
facts with the report that at the time of our American
Revolution a well-to-do family thought itself fortunate if
it had at most a barrel of potatoes for its winter supply,
and that these were only served on special occasions and
for honored guests, we can see how greatly the relative
importance of the position of the potato has changed.
The potato is a tuber, that is, an underground stem
which is thickened and has become a storehouse for future
plants. The eyes of the potato are buds from which the
new plants will sprout under proper conditions. These
new plants use the food material which is stored in the
potato, and the tuber itself is thereby gradually rendered
unfit for food.
CRUDE
FATOJfy
COMPOSITION OF THE POTATO
The average loss of nutrients from boiling is shown by the
shading.
If a thin slice across a potato is held up to the light, four
distinct parts are observable. First comes the grayish
brown skin, which corresponds with the bark of an ordinary
stem. Underneath this is the cortical layer, which may be
34
FOOD STUDY
from a tenth to a fifth of an inch thick, and is often slightly
colored. If this layer is exposed to sunlight for some
time, it will turn green, showing its relation to the green
layer which is found underneath the bark of an ordinary
stem. The inner layers are
known as the flesh of the
potato, and, for our pur-
pose, may be considered as
one. The potato is made
up of a network of cells;
| the cell walls being, of
course, largely cellulose.
The cells are filled with
water in which is dis-
SECTIONS OF THE POTATO
a, skin ; 6, cortical layer ; c, outer medullary layer ; d, inner
medullary layer.
solved mineral matter, a little sugar, and most of the
protein * which is found in the potato. In the cells and
surrounded by this water are the starch grains. While a
* Protein is the foodstuff containing nitrogen, and is essential
for building body tissue which contains nitrogen.
POTATOES 35
little fat is also present the amount is so small that it
need not be taken into consideration.
The potato is largely composed of water, seventy-eight
and three-tenths per cent, so over three-quarters of the
whole weight is water. Of the eighteen and four-tenths
per cent carbohydrate, about sixteen per cent is starch.
There is only four-tenths of one per cent of cellulose pres-
ent. Although they are small in amount, the two and two-
tenths per cent of nitrogenous matter and one per cent of
mineral matter are important.
Besides the substances already mentioned, there is also
a trace of solanin, a poisonous substance which may occur
in greater or less amounts and which is said to give the
characteristic flavor to the potato. This trace of solanin
is supposed to be volatilized during the cooking of the
vegetable, and so it is improbable that we ever eat it in any
large amounts. If the potato is old and has been allowed
to sprout, if it is unripe, or if it has been grown too near
the surface and so has a decidedly green color, it may
contain sufficient solanin to cause some digestive disturb-
ance. Instances of this, however, are probably very
rare. A fear of it makes us careful to cut away the flesh
immediately around the sprout in an old potato. Care
should also be taken to prevent sprouting, not only for
this reason, but because the sprouts use up the food ma-
terial in the tuber. Potatoes, then, should be stored in a
dark, dry, cool place, and should be protected against
freezing. A potato that has been frozen has a sweetish
taste and is never so mealy as a good potato.
Potatoes are distinguished as mealy, soggy, and waxy.
Most people prefer a mealy potato. This quality in the
vegetable is supposed to be due to the amount and dis-
tribution of the starch. If, however, in cooking, the steam
in a potato is allowed to condense to water, the potato
36 FOOD STUDY
becomes soggy. For this reason potatoes should never be
allowed to cease boiling while they are cooking; they
should be dried out as completely as possible when they
are done, and served in an uncovered dish. Baked
potatoes should be pricked with a fork or opened at once
when they are done. Some potatoes are naturally soggy,
but a good potato can be made so by poor handling in its
preparation for the table. New potatoes are much more
waxy than older ones, owing, perhaps, to the larger amount
of protein present.
Potatoes are sold both by measure and by weight, but in
many places dealers are now required to sell by weight,
because that gives a more uniform amount to the customer.
Potatoes should run fifteen pounds to a peck. In select-
ing, those of medium size and with a smooth skin should
be chosen. A large potato is more liable to break up in
cooking, and a small one means too much trouble in
preparation if it is to be pared.
In preparing potatoes for the table, they should first be
washed and then scrubbed with a small brush. If they
are to be boiled, they may or may not be pared before
cooking. If they are pared and then exposed to the air
for any length of time they will turn dark, owing to the
action of oxygen, together with a ferment which is found
in the potato. This can be prevented by dropping the
potatoes into cold water, which excludes the air. Soaking,
however, should be avoided, for it removes some of the
food material, which means loss of nutriment, and is only
permissible if the potato is rather old, wizened, or inferior.
In that case, the product is so much improved by the soak-
ing that we are justified, even though some food value is
lost. Since the cortical layer contains a higher percentage
of both the protein and mineral salts than the rest of the
potato, unless paring is carefully done we lose a large
POTATOES 37
part of the most valuable ingredients. If much fruit and
salad vegetables are included in the diet, it may not be
necessary to consider the loss of mineral salts ; but if it is
desired to preserve them, the potato should be cooked in its
jacket. This means that the potato is not quite so white,
but there is no special reason why a perfectly white potato
should be demanded. If potatoes are put on in cold water
to boil, the same effect as soaking is obtained. Most of
the mineral matter and protein, and some of the starch
are lost. If, instead, the potatoes are placed in boiling
water, the protein is coagulated quickly and less of it
escapes. Most of the mineral salts are still dissolved by the
water and so lost, since potato water has rather too strong
and disagreeable a flavor to be palatable and is usually
thrown away. Potatoes may be steamed with little loss
of nutriment, or baked, in which case practically nothing
is lost but water. Potatoes are cooked partly to hydrate
the starch, and partly because the expansion of water into
steam means the breaking of the cellulose walls of the
cells, whereby the contents become more readily digestible.
Probably the chief reason is the improvement of flavor.
Since potatoes contain a small amount of cellulose, com-
pared with most other vegetables, they are digestible, and
there is comparatively little difference in their digestibility
as a result of different ways of cooking. A mealy potato
seems to be more digestible than a soggy or waxy one,
probably because it is better broken up, and so the diges-
tive juices can get at it better. Potatoes have long been
classed as a starchy food, and most books state that there
is so little protein present that it need not be taken into
account. Max Rubner, in a recent paper, states that the
protein present is of such a character and amount as to
form a balanced ration, if it were possible to consume the
necessary bulk to supply the needed energy. Potatoes
38 FOOD STUDY
are so bulky, on account of the large amount of water
present, that they cannot serve as a sole food.
Sweet potatoes differ botanically from white in that they
are thickened roots instead of stems. Chemically, they
contain about nine per cent less water, and more carbo-
hydrate. Most of this additional carbohydrate is sugar,
which accounts for the sweet taste. Sweet potatoes
grown in different regions vary greatly in the amount of
sugar, those grown in the south containing a larger per-
centage than those in the north. There is so little differ-
ence in food value between sweet and white potatoes that
they may be substituted for one another in the diet.
REFERENCES
U. S. Dept. of Agriculture.
Farmers' Bulletin No. 244. "Cooking Quality of Potatoes."
Farmers' Bulletin No. 256. "Preparation of Vegetables for the
Table."
Farmers' Bulletin No. 295. ' 'Potatoes and other Root Crops as
Food."
Office of Exp. Station Bulletin No. 43. "Losses in Cooking Vege-
tables." "Comparison of the Digestibility of Potatoes and
Eggs."
QUESTIONS
1. Why should not potatoes be tightly covered while boiling?
2. How should they be cared for when done ?
3. Why are new potatoes more often cooked in their skins or
jackets than old potatoes ?
4. When do new potatoes come into market ?
5. What is the average cost of potatoes ?
6. Is it fairer to sell potatoes by weight or measure? Would a
bushel of very large potatoes or of very small potatoes give the pur-
chaser most for his money ?
7. How should potatoes be kept to prevent sprouting? What
harm does the sprout do the potato ?
8. Are old or new potatoes considered more digestible? Why?
USE OF WATER IN COOKING 39
9. If you are going to use the potato mashed, what is the advan-
tage of cutting the potato into slices before cooking? What is the
disadvantage ?
10. Why should potatoes be pared as thinly as possible without
too great waste of time? Where do the mineral salts in potatoes
lie?
11. If the potatoes you wish to boil together are not all one size,
what will you do ?
12. Compare the temperature you obtained for boiling water with
the temperatures to be obtained at sea level, and on high mountains.
Explain the variations.
VII
USE OF WATER IN COOKING
BOILED EGGS
STUFFED EGGS
A. Class Experiments. EGGS.
1. Weigh out a pound of eggs. How many average-
sized eggs in a pound? Repeat with small eggs.
With large eggs. Would it be fairer to sell eggs
by the pound instead of by the dozen?
2. Boil an egg in a strong solution of cochineal for
half an hour. Break open and examine. What
property of the shell is shown? What problem
does this present in the care of eggs?
3. Tests for freshness.
a. Place eggs in a ten per cent salt solution.
What is the relation of the freshness of an egg
to its specific gravity ?
b. Roll up a large sheet of paper into a cylinder.
Place an egg in one end and look through
the other end. Hold in front of a strong
40 FOOD STUDY
light. What may a dark appearance indi-
cate?
c. Note the feeling of the shell, rough or smooth.
d. Shake various eggs.
Are all these tests reliable with cold storage
eggs?
B. Class Experiment.
COOKING TEMPERATURE OF WHITE OF EGG.
1. Put a little white of an egg into a test tube and im-
merse the test tube in cool water above the level of
the egg inside. Hold a thermometer in the egg white,
and heat the water gradually, watching the egg
carefully. As soon as it becomes opaque remove the
tube from the water and note the temperature.
Try some of the egg, and notice how tender it is.
Replace the test tube with the rest of the egg white
and heat as long as the temperature rises. Remove
and compare with the first.
2. Cook an egg in boiling water for three minutes.
Cook another by keeping it five minutes in water
just below the boiling point (about 175 F.). Break
and compare consistency.
3. Boil an egg for twenty minutes. Compare with an
egg kept in water just below the boiling point for
forty-five minutes.
C. Class Experiment. BOILING EGGS.
1. Place three eggs in three pints of boiling water.
Cover closely to retain heat, but remove from flame-
Remove :
a. one egg in five minutes,
b. one egg in seven minutes,
c. one egg in ten minutes.
WATER 41
2. Give directions for cooking correctly :
a. a soft-cooked egg,
b. a medium-cooked egg,
c. a hard-cooked egg.
D. PREPARE STUFFED EGGS.
Cut a hard-cooked egg in halves ; carefully remove the
yolk. Season the yolk by mashing and mixing with it
| tsp. vinegar A pinch of salt
1 ssp. mustard A few grains of paprika
Add melted butter, about a fourth of a teaspoon, so that
the yolk can be molded, shape into balls, and refill the
whites. Cheese or minced ham may be added to the yolk.
WATER
Water, as everyone knows, exists in three states or
conditions. It may be solid, in which case it is called ice ;
it may be liquid, and then it is really called water ; or it
may be a vapor, in which case it is spoken of as steam.
The difference between these states is merely one of tem-
perature. It takes heat to turn ice into water, and it takes
heat to turn water into steam. Since water cannot, under
ordinary circumstances, grow any hotter than its boiling
point, cooking will not proceed any faster because the
water is boiling fast instead of slow. All that is accom-
plished is the turning of more water into steam. If the
object is the concentration of the material, then it is of
course desirable to boil fast ; but in most boiling it means
merely a waste of heat. Occasionally the rapid motion is
itself desirable, because it keeps the food from settling
to the bottom of the pan and perhaps burning. The
pressure cooker is a device for retaining the steam and so
42 FOOD STUDY
increasing the pressure that the water itself actually is
hotter than the usual boiling point. Food can, of course,
be cooked faster in it than in the usual covered kettle,
because the temperature is really higher.
Water is used in more than one way in cooking. Some-
times it acts as a carrier of flavor, as when it is used to
extract the flavor of tea or coffee ; sometimes as a means
of conveying heat to the food to be cooked. This is its
use in boiling or steaming. At other times water is taken
up into the food itself. In cooking rice, for example,
there is much starch present but not enough water to
hydrate it. This is the reason that rice cannot be put in
an oven and baked as a potato can.
Water is composed of two gases, oxygen and hydrogen.
It is true that some water is actually manufactured in the
body by the oxidation of some of the hydrogen contained
in food, but as the water we consume as such is never
broken up in the body into these two gases, it is not neces-
sary to consider further its chemical composition.
Although water is not capable of furnishing the body
with energy, it is absolutely necessary to us. While
people have proved that it is possible to go without food
for weeks, it is impossible to live any length of time with-
out water. The body itself is about two-thirds water.
This\neans that there must be water to build up into body
substance. Besides this, water has many important
functions. For example, it moistens the digestive tract ;
makes it possible to swallow food ; softens the food itself ;
mixes with the digestive ferments, and so enables them to
act upon all parts of the food. It dissolves the food as it
is digested and carries it through the lining of the digestive
tract. Then, the blood is composed largely of water, as
are all the other fluids of the body ; so it is water that
carries nourishment to all the different cells in the body.
WATER 43
Water in the blood circulating through the body acts as a
distributor of heat, and, again, the evaporation of water as
perspiration helps to regulate the heat of the body. It is
water, too, that dissolves and carries away the wastes of
the body. But these are only some of the important func-
tions of water. It is probable that none of the chemical
and physiological changes which go on in the body can
take place except in the presence of water.
The body gives off from the lungs, skin, and kidneys
about four and one-half pints of water daily. About one-
sixth of this amount is the water that was spoken of as
manufactured from the oxidation of food ; the remaining
amount must be taken into the body daily. Of course,
a good deal of water is furnished by foods themselves.
Soups and beverages obviously contain large amounts of
water, but many other so-called solid foods, like potatoes,
contain large amounts. It is usually said that a person
needs about eight glasses of liquid a day.
At one time it was considered harmful to drink water
with meals, for it was feared that the water would dilute
the digestive juices to such an extent that they would fail
to act upon the food. This notion is still popularly be-
lieved. Recent experiments, however, were tried to
determine the truth of the matter. Healthy men were fed
test meals, in some cases water being given and in others
withheld. After a certain length of time, the contents of
the stomach were examined to see how fast digestion had
proceeded. In every case it was discovered that digestion
took place more quickly if water had been given. We know
now that the taking of water at meals is beneficial, stim-
ulating digestion and not hindering it. What has been
said is not in any way intended to imply that the washing
down with water of poorly chewed food is anything but
harmful. That is an entirely different question; nor
44 FOOD STUDY
is it intended to imply that the drinking of large quantities
of very cold water may not have a different effect from
the one described. Cold stops digestion, or slows it,
and too much ice water at a meal may readily have
this effect.
People who wish to grow thin are often told to go with-
out water at meal times. The reason this is an aid is not
that water itself is fattening, but because less is eaten if no
liquid is taken. The same effect would be accomplished
if we should in any other way lessen the amount eaten.
Anyone going without water at meals should be sure to
drink the needed amount of water between meals, for
water is just as necessary to him as to anyone else.
Water is usually classified as surface and ground water.
Rain water and water from streams and rivers belong to
the first class. Well water and deep spring water belong
to the second. Rain water is our purest water, if it is col-
lected from a clean surface after the dust in the air has
been washed out. This water, flowing along the ground or
through it, dissolves or carries along with it many different
substances. Water which has much mineral substance
dissolved in it is called hard ; this is the water that will
not lather easily with soap. Hard water is, however, of
two kinds. In one case there is present a soluble lime
salt which precipitates if the water is boiled. This is the
water which leaves a crust on the inside of a tea kettle.
It is called temporarily hard because the water itself is
softer after the boiling. Water containing salts of lime
and magnesium which are unaffected by the boiling is
called permanently hard. Permanently hard water may,
however, be softened by the addition of such chemicals as
soda, ammonia, and borax. Soft water is much the best
for washing and also for cooking, but it is not so palatable
as harder water. Water that is very hard is possibly not
WATER 45
so good for us. If it can be softened by boiling, it may be
cooled and used for drinking.
Water is a carrier of bacteria, and the most harmful
water is not hard water, but water which contains harm-
ful bacteria. There are many kinds of domestic filters
which are supposed to remove the bacteria from the
water. Most of them are not reliable and, in any event,
need great care. They must be sterilized frequently or
the water which goes through them will be found to con-
tain more bacteria than it did before. If there is any
reason to believe that the water is dangerous, it is much
safer to sterilize the water by boiling it. All that is
necessary is to bring the water to boiling and then cool it.
Water which has been boiled tastes flat because it contains
less air dissolved in it. The palatability can be increased
by pouring the water back and forth from one pitcher to
another so as again to dissolve air in it.
Freezing does not sterilize water. While in cities, at
least, our water usually comes from a reservoir that is
carefully protected from contamination, our ice supply
may come from a private pond in which the water may
be quite impure. Unless it is known that the water
from which the ice was made was pure, the ice itself should
not be put into beverages or foods. Instead, they can be
set on ice to cool. So-called artificial ice is manufactured
by freezing water in large tanks, the necessary cold tem-
perature being often obtained by the evaporation of
ammonia. Such ice is as pure as the water from which it
is made.
REFERENCES
U. S. Dept. of Agriculture. Bulletin 57. "Water Supply, Plumb-
ing and Sewage Disposal for Country Houses."
OGDEN. "Rural Hygiene."
46 FOOD STUDY
QUESTIONS
1. What diseases are most frequently carried by water?
2. Why is the water from shallow wells often dangerous ?
3. How should such wells be protected ?
4. Why is deep well water usually safer ?
5. How is the question of sewage disposal bound up with the
question of a safe water supply ?
VIII
USE OF WATER IN COOKING
POACHED EGGS
A. Class Experiment. SOLUBILITY OF EGG WHITE.
1. Cut a small piece of uncooked egg white with a
pair of scissors. Shake the egg white with some cold
water. Filter. Has any of the egg white dissolved ?
Find out by testing as follows :
a. Boil some of the filtered water.
What happens ?
b. Add nitric acid to a second portion and boil.
Cool, and add ammonia. Note color given.
c. Try the effect of the acid and ammonia on some
of the egg white itself. Egg white contains
large amounts of protein, and protein gives the
color with the acid and ammonia.
2. Repeat the experiment, but use water which is nearly
boiling to shake with the egg.
E. Class Experiment.
THE CORRECT TEMPERATURE FOR POACHING EGGS.
1. Drop one teaspoon of egg white into a pan of water
which is at about 150 F.
EGGS 47
2. Repeat, but have the water boiling hard and let it
continue boiling for a moment or two.
3. Repeat, but have the water just below boiling.
Why does the egg white spread in one, and break up
in another? In which is the temperature too high to
give the cooked egg a good consistency?
C. POACH AN EGG. From the results obtained in
the previous experiment, account for the temperature of
the water suggested in the following recipe. While it
is desirable, the muffin ring is not essential. Serve on
toast. What will happen if the water used is too cold?
Too hot?
DROPPED EGGS. (Poached)
Have ready a shallow pan two-thirds full of boiling,
salted water, allowing one-half tablespoon of salt to one
quart of water. Put two or three buttered muffin rings
in the water. Break each egg separately into a cup, and
carefully slip into a muffin ring. The water should cover
the eggs. When there is a film over the top, and the white
is firm, carefully remove with a buttered skimmer to cir-
cular pieces of buttered toast, and let each person season
his own egg with butter, salt, and pepper.
From the "Boston Cooking-School Cook Book." By
FANNIE M. FARMER.
EGGS
The United States government bulletin on eggs tells us
that "perhaps no article of diet of animal origin is more
commonly eaten in all countries or served in a greater
variety of ways." But eggs are even more interesting
when it is remembered that, like milk, they are a complete
food intended for the sole nourishment of the young
48 FOOD STUDY
animal. They must, of course, contain everything that is
needed for growth. Even after what has been said about
the need for water, it may be a surprise to learn that the
edible portion of eggs is about three-fourths water, averag-
ing about seventy-four per cent. The amount of protein
present is high, fourteen and a half per cent; and this,
together with the large amount of fat, ten and a half
per cent, makes eggs rank with milk and meat in the
diet. Then the ideal form of the iron and phosphorus
present in the mineral matter adds to the value of eggs
from the dietetic standpoint, and they are probably even
better building material than meat. This nutriment is
not divided evenly between the white and yolk, for the
white contains more water and less protein and mineral
matter than the yolk ; and practically all the fat is found
in the latter. This highly nutritious yolk is intended to be
the first source of food for the embryo chick. This embryo
can usually be seen as a tiny dark speck lying close to the
yolk. The white is food used at a later stage.
The problem in buying eggs is to obtain them fresh,
and the term fresh is by no means the same as new-laid.
The new-laid egg is, of course, the most desirable grade,
but often can be had only at an exorbitant price quite
beyond the pocketbook of the average person. Eggs,
like other foods, are affected by bacteria. The shells are
a partial protection, but since they are porous, bacteria
can enter and soon begin the process of decay. The
earliest change is mainly in flavor. Later, the membrane
which surrounds the yolk is partially absorbed and it be-
comes difficult to separate the yolk from the white. The
white can never be beaten stiff and dry if part of the yolk
is mixed with it. An egg kept too long in cold storage often
will have a white which will not beat properly.
As eggs do not keep long under usual conditions and as
EGGS 49
hens do not lay uniformly throughout the year, many
methods of preserving eggs have been tried. The most
successful method for home use is a water-glass solution.
This substance, which is a silicate of potassium or sodium,
or a mixture of the two, can be bought as a syrupy liquid
at a few cents a pound and diluted with ten times its volume
of water. The water used should be pure and is better
boiled and cooled before mixing. The diluted water-glass
is poured over the eggs so as to cover them completely, and
then they must be put into a cool place. This method is
not only the easiest to use, but also the one that keeps the
eggs best and with least disagreeable flavor. Eggs laid
in April, May, and June are the best to use for this pur-
pose, as they seem to keep most satisfactorily. The best
method of all for keeping eggs is cold storage, and such eggs
in certain seasons are about all that are on the market.
Eggs which have been kept in this way will rattle some-
what when shaken, because of the evaporation which
may have gone on, and yet be fresh enough for use.
Eggs should be washed before use. As the mucilagi-
nous substance on the outside of the shell helps to render
it less porous, it is better not to wash the shell until the
egg is to be used.
Eggs are becoming costly, and it is necessary to consider
this in their use. Many recipes which call for eggs for
thickening can be modified so that flour or starch may be
substituted for all or at least some of the eggs, and baking
powder may take the place of the egg used for leavening.
For most people eggs are an easily and completely
digested food. Sometimes an uncooked egg swallowed
whole causes disturbance, because it has not sufficient
flavor to start the flow of the digestive juices, and since
the egg is not broken up, what ferment is present cannot
well get at it. A raw egg beaten up with a little milk is
50 FOOD STUDY
much less apt to cause trouble. Eggs cooked in any way
are very completely digested, and the ordinary person does
not have to consider the small differences in digestibility
which result from different methods of cooking. Even
hard-boiled eggs, if they are not swallowed in lumps
instead of being properly masticated, can be included in
this statement. A soft-cooked egg is, however, more
acceptable to most people than one that is hard-boiled.
REFEKENCES
U. S. Dept. of Agriculture.
Farmers' Bulletin No. 87. "Food Value of Eggs."
Farmers' Bulletin No. 103. "Preserving Eggs."
Farmers' Bulletin No. 122. "Selling Eggs by Weight." "Flavor
of Eggs."
Farmers' Bulletin No. 128. "Eggs and their Use as Food."
Farmers' Bulletin No. 190. "Cost of Eggs in Winter."
Cornell Reading Course. "Preservation of Foods," Pt. Ill, pp.
299, 300.
Connecticut Exp. Station Bulletin, No. 55. "Infection and Preser-
vation of Eggs."
Office of Exp. Station Bulletin, No. 43. "Comparison of Digesti-
bility of Potatoes and Eggs."
QUESTIONS
1. How can the freshness of an egg be determined before
breaking ?
2. Why does an egg become stale ?
3. Are cold-storage eggs good food ?
4. What is the best method of preserving eggs at home ?
5. Why should eggs that are to be kept for some time not be
washed before being put away ?
6. Why must precaution be taken against putting eggs away
near strong-smelling foods ?
7. Why should eggs be washed before breaking ?
8. What use is made of egg shells ?
9. How many eggs of average size in a pound ?
USE OF WATER IN COOKING 51
10. What were the maximum and minimum prices of eggs during
the past year ? At what season of the year are eggs most expensive ?
Cheapest?
11. Why are eggs valuable as food?
IX
USE OF WATER IN COOKING
CEREAL BREAKFAST FOODS
A. Class Experiment.
THE RELATION OF SURFACE TO EVAPORATION.
1. Put equal amounts of water into two saucepans, one
much larger than the other, and heat both the same
length of time, until the water in one is about half
gone. Cool and measure roughly the amount of
water left in each. To what, besides time, is the rate
of evaporation proportional ? Would you increase or
decrease the amount of water to be used in cooking
a small amount of cereal in a large pan?
2. Repeat the experiment, but with the saucepans
closely covered. Is there any difference? Explain
the result.
B. PREPARE CEREAL WITH FRUIT.
1. Add gradually two tablespoons of wheatena to a cup
and a quarter of actively boiling water, to which one-
sixth of a teaspoon of salt has been added. After ten
minutes cooking over the direct flame, finish over hot
water. This will probably take thirty minutes. A
few moments before the cereal is done, add the meat
of five dates cut very fine. Serve with sugar and
cream.
52
FOOD STUDY
U&Doportmert of Agriculture
Office of Experment Stations
AC.True. Director
rrepGrea by
ORTW
C.ELANGWOR1...
Expert in Charge of Nutrition Investigation
COMPOSITION OF FOOD MATERIALS
omD E%^? R^ mrm rarpueivoiw
Water
Fat Carbohydrate* Ash
CORN
Fat: 4.3
'ater:10.8
Water: 10,
FVotein:1
WHEAT
at:1.7
AA15-W ""-l-' 73 * Carbohydrates., ^ 5^^^ t .Q
FUEL VALUED FUEL VALUCT
BUCKWHEAT
ISOOcALDRCS Rrxjtan:10.0L^rWater:12.6 1750
PER POUND ~ . , __JH^Fat:2.2
:ALORIES Water: 1
Protein?
RICE
1720 CALORIES
PER POUND
Car
:10^
12 -2 Fua VALUE:
1720 CALORtt
PCR POUND
1750 CALORIES
PER POUND
COMPOSITION OF CEREALS
CEREAL BREAKFAST FOODS 53
2. Repeat (1) to the point where the cereal has been
cooked over the direct flame, but use only five-sixths
of a cup of water. Then, instead of finishing over
water, place it in a fireless cooker or hay box.
C. Class Experiments. CEREALS.
1. Test cereals for both starch and protein.
2. Examine rice- and oat-starch under the micro-
scope. Notice size, shape, and any apparent
markings.
CEREAL BREAKFAST FOODS
Cereals are cultivated grasses, but the seeds of these
grasses are often called cereals. Sometimes, the term
includes all products of cereals such as flour and macaroni
as well as the grains themselves. Common usage, how-
ever, often makes the word cereal synonymous with break-
fast food. The seeds of the cultivated grasses are the part
of the plant used, because they are packed with nutriment
for the embryo. The grains commonly used for breakfast* 1
food are wheat, oats, corn, rice, and, occasionally, barley.
Rice contains a larger amount of starch than the others,
but little fiber, and it is on this account easily digested.
Of the three grains most commonly used for breakfast
foods, wheat, oats, and corn, oats furnishes most protein
and fat, and has the highest calorie value * per pound.
Wheat, however, does not differ very greatly in nutritive
value and contains less fiber and so is more easily digested.
Corn has a very tough fiber and ranks below the other two
in calorie value. All these differences are comparatively
small, and we can rank cereals together in their place in
the diet, with the following average composition :
* The calorie value of a food is the amount of energy, meas-
ured in calories, which a given food furnishes to the body.
54 FOOD STUDY
Water 10-12 per cent.
Protein 10-12 per cent.
Carbohydrates 65-75 per cent.
Fat 2-8 per cent.
Mineral Matter 2 per cent.
These figures are for the raw grains. Mushes and
porridge contain a great deal of water. Cooked oatmeal
contains nearly eighty-five per cent of water, but shredded
wheat and the flaked breakfast foods have practically the
same composition as the original grains.
The cost of breakfast foods varies somewhat with the
cereal from which they are made, the cost of those made
from corn being least, those from oats next, while wheat is
the most expensive. Cost, however, differs even more
with the amount of preparation that has already been
made. From this point of view, breakfast foods may be
divided into four classes. In the first are foods like oat-
meal or cracked wheat in which the grain has been husked
but not cooked. Next, comes the class of partially cooked
foods. These have been steamed until they are somewhat
softened and then, if they are to be put on the market as
flakes, they are passed between hot rollers which flatten
the kernels. Rolled oats is an example of this class. The
third class is composed of those which are sold ready to
eat, as grape nuts or shredded wheat. Sometimes malt is
used in the process of manufacture and is supposed to
change the starch into sugar and so start the process of
digestion. In most breakfast foods which are malted, not
much change in the starch will be found to have occurred,
and since, for the healthy person, it is of little moment
whether this change has occurred or not, this fourth class,
called predigested, is not of great importance. Breakfast
foods which belong to the third class cost much more per
pound than those in the first class, because more trouble
CEREAL BREAKFAST FOODS 55
has been taken in the preparation. The advantage to the
housewife is in the saving of time necessary to prepare the
food. Foods of the first class need to be cooked many
hours in order to render them thoroughly digestible. This
is more or less trouble even on a coal or wood stove, and on
a gas stove is an expensive process. Cereals can, however,
be easily and cheaply prepared in a fireless cooker, and if
both cost and attention are to be considered, this is the
method of preparation which should be chosen. The foods
of the second class need, usually, to be cooked about twice
as long as the time given on the package. The manufac-
turer, in order to attract custom, cuts the necessary time
of preparation down to a minimum.
Many of the breakfast foods may be purchased both
in bulk and package. The advantage of the package is
greater surety of cleanliness. Most of the milling is
carried on under excellent sanitary conditions. The
package assures us that the goods have come to us in the
same condition as that in which they left the mill. Bulk
goods are often protected neither from dust nor insects.
As, however, the uncooked cereals sold in bulk are
thoroughly sterilized in cooking, this protection is far less
necessary than in the case of such foods as bread, which is
eaten as bought.
Since cereals do not keep well, it is better to buy them
only in moderate amounts. There is often considerable
saving, however, in buying even two packages instead of
one.
REFERENCES
U. S. Dept. of Agriculture.
Farmers' Bulletin No. 105. "Cereal Breakfast Foods."
Farmers' Bulletin No. 237. "Cereal Breakfast Foods."
Farmers' Bulletin No. 249. "Cereal Breakfast Foods."
Farmers' Bulletin No. 316. "Cooking Cereal Foods."
56 FOOD STUDY
Fanners' Bulletin No. 298. "The Fireless Cooker."
The Exp. Station Bulletin No. 200. " Course in Cereal Foods."
QUESTIONS
1. Make a list of all the kinds of grain you know.
2. How does the English use of the word "corn" differ from the
American ?
3. Give illustrations of the different groups of breakfast foods on
the market.
a. Uncooked grains.
b. Partly cooked.
c. Ready to eat.
d. Predigested.
4. What are the advantages and disadvantages of the different
groups ?
5. Is the greater cost of package foods justified?
6. Why is it well to keep cereals in glass jars tightly covered ?
7. Why are cereals so important as food ?
8. How can the "skin" which sometimes forms on top of a cereal
while it is cooking be prevented ?
9. Why will soaking the grains for an hour or so beforehand shorten
the needed time for cooking ?
10. What are the advantages of using a fireless cooker in preparing
cereals ?
STARCH
APPLE TAPIOCA
BOILED RICE
A. PREPARE APPLE TAPIOCA.
1| tbsp. Minute tapioca
c. water
A pinch of salt
Cook together in a double boiler until transparent (about
fifteen minutes). Pare and core a sour apple. Put in a
buttered baking dish, and fill the cavity in the apple with
STARCH 57
sugar. Pour the tapioca over it, and bake in a moderate
oven until the apple is soft. Serve with sugar and cream.
B. RICE.
Wash the rice thoroughly in a strainer in a bowl of water,
rubbing the rice between the hands. Change the water,
until it remains clear. Cook by the following methods:
1. Gradually sprinkle two tablespoons of rice into two
cups of rapidly boiling water with one-half teaspoon
of salt added.
2. Cook two tablespoons of rice in two-thirds of a cup of
boiling, salted water for five minutes. Finish cook-
ing in a double boiler. (Why is less water used ?)
3. Cook two tablespoons of rice in two-thirds of a cup of
boiling, salted water for five minutes. Then place in
a mold and steam.
In all cases cook until the rice is soft.
a. Compare the time used to cook by the different
methods.
b. Compare the appearance of the kernels as a result
of the different treatments.
c. Note also the relative amounts of rice before and
after cooking.
STARCH
Starch occurs in the cells of all plants as tiny white
granules, but the size, shape, and appearance of these
differ with the kind of plant from which they are taken.
A plant manufactures sugar from the carbon dioxide in the
air and from water, and this sugar is used as nutriment for
the plant, being dissolved in the juice or sap and circulating
through it. But since the plant has to store some of this
nutriment for future use, it manufactures starch from some
of the sugar. Starch has the advantage over sugar that
58 FOOD STUDY
it is not soluble in water. The material is carried into the
cell as a solution of sugar which can pass readily through
the cell wall and is then turned into granules of starch.
When the starch is finally used as the plant food, this
process is reversed, the granules change into sugar again,
and can then pass out through the cell wall.
Scientists do not agree entirely in regard to the construc-
tion of starch granules, but they believe that they are
made up of at least two kinds of starch which are some-
times named red and blue amylose. Amylose is merely
the scientific name for starch, and the names red and
blue are given to the two kinds not at all because of their
color, for they are both white, but because of the colors
which they turn with iodine. The starch inside the
granules and composing the greater part of the grains is
blue amylose, easily digested. Its outer covering is red
amylose, much more difficult of digestion and impervious
to cold liquids. If the starch grain is heated in water, it
begins to swell, till its outer covering is stretched thin and
allows liquids to pass readily through it. In this form
digestive juices can get at the starch inside to digest it;
and, therefore, cooked starch is more digestible than raw.
Starch granules found in potato and arrowroot seem to
be made up of only these two kinds of starch, but those in
cereals seem to contain a small amount of a third kind
called rose amylose. This is more difficult of digestion
than is either of the other kinds, but with long boiling can
be made to change into blue amylose. As it seems to
be rather hard to cook the starch granules when they are
shut up in the cell walls of the seed, this may be the reason
why cereals take such a long time to cook. Corn starch is,
of course, a cereal starch, and ordinary wheat flour, too,
contains an abundance of starch; but in grinding the
grains, the cell walls are broken and so there is not the
Rice Starch
Wheat Starch
STARCH GRAINS, MAGNIFIED MANY TIMES
From Leach's "Food Inspection and Analysis."
STARCH
59
same difficulty in getting at the starch for cooking. If,
during the cooking of starch, as, for example, in the cooking
of oatmeal, the surface is left exposed so that the top dries,
the starch is changed into a hard skin which is exceedingly
difficult of digestion. If the oatmeal is stirred occasion-
ally and kept covered so that the steam is confined in the
space above the surface, no such change occurs.
When a vegetable food containing much starch, such as
potatoes or cereals, is cooked, the starch granules swell in
the process until they burst most of the cell walls of the
plant.
CHANGES OP STARCH GRAINS IN COOKING
a, cells and starch grains in a raw potato ; 6, in a partially
cooked potato ; c, in a thoroughly boiled potato.
Starch is not soluble in cold water, but, when heated, the
granules finally break down and gelatinize. This is only
partial solution. When a substance really dissolves, it
disappears entirely from view, as sugar does in water. It
may impart a color to the solution, but it does not render
it opaque. Because starch does not dissolve, it cannot
pass through the lining wall of the intestines and so must
be changed in digestion before it can be absorbed. A
ferment called ptyalin is found in the saliva, which is
capable of acting on starch and changing it to sugar.
There is an intermediate stage in this action, for the starch
60 FOOD STUDY
is first changed into dextrine. Dextrine is whitish like
starch, but with iodine turns a beautiful wine red. Unlike
starch, it is soluble in cold water. When starchy food is
chewed saliva is mixed with it, and as the food lies in the
fundus (or middle part) of the stomach the ptyalin has a
chance to act on it. It used to be thought that this
action stopped as soon as the food reached the stomach, for
ptyalin cannot act in gastric juice, but it is now known
that this change can go on for about two hours before the
gastric juice is so mixed with the food that the action is
stopped. Therefore it seems a somewhat important
matter that such food should be chewed thoroughly and
mixed with saliva and not swallowed whole or washed
down with liquids. In the stomach, however, not all of
the starch is digested. Probably most of it does not go
beyond the dextrine stage.
In the intestines there is another ferment, sometimes
called amylopsin, which, like the ptyalin, can digest starch.
We are, then, apparently, well equipped to digest starch,
and this is fortunate, for starch forms a large proportion
of the nutrients of our diet.
Dextrine may also be formed by heating dry starch very
hot, at least to 320 F. It is formed somewhat in toast,
and in the crust of bread, and in browned flour, since in
these cases the starch is exposed to intense heat. Some
breakfast foods are partially dextrinized and this is sup-
posed to make them more digestible. In reality, so small
a percentage of the starch is changed that they are really
not very different.
Browned flour does not possess the thickening power of
ordinary flour because the dextrine in it dissolves instead
of gelatinizing. Since heating with acids will dextrinize
starch at a much lower temperature, and only a few drops
of acid are necessary to bring this about, it is sometimes
J^[^
Pea Starch
Bean Starch
Buckwheat Starch Potato Starch
STARCH GRAINS, MAGNIFIED MANY TIMES
From Leach's "Food Inspection and Analysis."
STARCH 61
possible to obtain this result when it is unexpected and
undesired. When a lemon filling for a pie or a boiled
dressing that is made with flour are cooked too long or
with too much acid, they may grow thinner instead of
thicker as the cooking continues. So, also, if creamed
oysters are kept hot too long a thick white sauce may
become very thin.
REFERENCE
U. S. Dept. of Agriculture. Exp. Station Bulletin No. 202. "The
Digestibility of Different Kinds of Starches ... as Affected
by Cooking."
QUESTIONS
1. Where does a plant obtain the necessary elements to make
starch ? How does it take in water ? How does it get carbon ?
2. What purpose has the plant in manufacturing starch, and in
what parts of plants would you expect to find the largest stores of it ?
3. How is rice grown, and where do we obtain our largest supply?
4. What is the composition of rice? Why is it not used as an
exclusive diet ?
5. What is the difference in price of different grades of rice, and
to what is this due ?
7. Why not bake rice as we do potatoes ?
62 FOOD STUDY
XI
RICE AND INDIAN PUDDINGS
COST OF BREAKFAST FOODS
A. PREPARE RICE PUDDING.
c, steamed rice 1 tbsp. sugar
\ c. milk \ tsp. salt
\ egg 2 tbsp. raisins
Scald the milk before using it. Beat the egg with salt,
add sugar, and pour the scalded milk over the mixture.
Put into a buttered baking dish with rice and raisins.
The raisins may be omitted and a little grated rind of a
lemon used ; or cinnamon, ginger, or nutmeg. Molasses
or maple syrup may be substituted for the sugar. Or :
PREPARE INDIAN PUDDING.
Use one tablespoon of Indian meal to one cup of milk
and other ingredients in proportion.
5 c. scalded milk \ c. molasses
J c. Indian meal 1 tsp. salt
1 tsp. ginger
Pour the hot milk over the meal, and cook twenty minutes
in a double boiler. Add the other ingredients, and bake
very slowly in a buttered dish.
B. CRISPED CEREALS.
Examine and taste a " ready-to-eat " cereal as it is pur-
chased. Place a little of it in a pan and put it for a moment
in an oven ; compare with the portion not heated.
C. COST OF BREAKFAST FOODS.
Take packages of well-known cereals. Determine how
much of each must be used for one serving, then how many
CELLULOSE
63
servings each package will give. Calculate the cost of a
serving of each, and fill in the following table.
NAME OF CEREAL
COST
OP PACKAGE
AMOUNT
OF ONE
SERVING
NUMBER OF
SERVINGS
IN A
PACKAGE
COST
PER
SERVING
COST
PER
OUNCE
CELLULOSE
Cellulose is the fiber which makes up part of the frame-
work of vegetable foods. It has the same chemical com-
position as starch, but is much less soluble, and human
food contains only a small percentage of it. It is a form of
carbohydrate which is of less importance to mankind than
to animals. While animals have ferments in the digestive
tract which are capable of digesting cellulose, none with
this power are secreted by man. Nevertheless, the scien-
tists find that man digests some cellulose. This is one
of the beneficial acts of bacteria present in the intestines.
These bacteria are capable of acting on tender cellulose
and changing it, perhaps into sugars and organic acids,
in which forms it can be absorbed and burned as fuel to
furnish the body with heat and muscular energy. Un-
doubtedly some of the breaking down of the cellulose
proceeds further than this, and hydrogen and other gases
are produced which have no nutritive value.
64 FOOD STUDY
But not all forms of cellulose are easily enough broken
down to have such changes occur. Cotton is a form
of cellulose which would be absolutely without nutritive
value. Such tender cellulose as is found in the cell walls
of seeds like the cereals, and in vegetables, especially when
young, is more capable of being digested. Still, it is
probable that the less cellulose there is present in a vege-
table food, the more digestible it is. This is probably the
reason that rice is so easily digested, for it contains less
cellulose than the other grains.
Boiling in water does not change real cellulose at all,
just as cotton clothes are not changed by boiling. But the
cellulose cell walls of a plant are stiffened with other re-
lated substances ; for one, with the pectose which changes
to pectin. Cooking dissolves out some of these inter-
cellular substances and also hydrates the starch, and so
cooked vegetables are softened. Then, as has already been
explained, by thorough cooking the cellulose walls may
be ruptured by the swelling of the starch grains within the
cells and so the contents exposed without its being neces-
sary first to digest the cell walls.
Some authorities believe that inert particles like cellu-
lose are sufficiently rough to stimulate the intestines to
peristaltic action, that is, to movements which hasten the
passage of food through the intestines and which are an
aid in combating constipation. But, since foods are not
laxative in proportion to the amount of cellulose they
contain, others believe this action is due rather to the
stimulus of certain salts which occur largely in the husks
of the cereal ; and that it is due to the presence of these
salts and not to the larger amount of cellulose in them that
such articles of food as cracked wheat and graham bread
are more laxative than those cereals which have undergone
more extensive manufacturing processes.
MINERAL AND ORGANIC SALTS 65
MINERAL AND ORGANIC SALTS
Mineral matter occurs not only in the teeth and bones,
but in every tissue of the body and in all the fluids. It is
necessary in all the vital processes. The principal mineral
elements in the body are calcium, magnesium, iron, sodium,
potassium, phosphorus, chlorine, iodine, fluorine, silicon,
and sulphur. These occur as compounds, forming both
mineral and organic salts. Unlike carbohydrates, fats,
and proteins, mineral salts are not changed in digestion
nor are they oxidized, and so they do not furnish the body
with energy. When organic matter is burned, these salts
remain unconsumed as the ash.
Mineral matter is present in all the digestive juices and
plays its part in the digestion and absorption of foods.
Mineral matter is dissolved in the blood and regulates its
specific gravity and its alkalinity. It is found in all
tissues, where it is concerned in metabolism.* Mineral
matter, too, probably stimulates the contractions which
cause the heart to beat.
Since man excretes every day a large amount of mineral
matter, this loss must be replaced. The necessary amount
of mineral matter is found in an ordinary mixed diet.
Common salt, sodium chloride, is the only mineral which
is added to food, but it is probable that there would be
enough of this furnished in the food of a mixed diet. In
fact, it is possible that large quantities of salt are really
bad for us rather than helpful. People, like the Esqui-
maux, who are unaccustomed to its use easily detect the
addition of an exceedingly small amount and dislike it, but
those who are habituated to its use crave it. Salt seems
to accentuate flavor.
* Metabolism includes all the processes which food undergoes
after it is digested and absorbed and before it is excreted.
66 FOOD STUDY
In the metabolism of proteins, mineral acids are formed
which must be neutralized by such basic substances as
sodium, potassium, calcium, and magnesium, in order to
preserve the alkalinity of the blood. As these basic
elements are abundant in vegetables and fruits, it is neces-
sary that the diet should contain liberal amounts of both
and not consist too largely of meat. The modern diet is
likely not to be well balanced in this respect, because it
consists of liberal amounts of meat, fats, and sugar, all of
which contain insignificant amounts of mineral salts.
At first thought it seems strange that fruits should be
added to prevent over-acidity when fruits themselves are
acid; but the acids present are organic acids, such as
citric, malic, tartaric, and oxalic. Some of these are
decomposition products of starch and are oxidized by the
body to produce energy and are then given off as carbon
dioxide and water, just as starch is metabolized. Mineral
acids cannot be oxidized in the body and must be neutral-
ized into salts and then excreted, and that is why they
require basic elements with which to unite to become salts.
It is important to remember the need for generous
amounts of vegetables and fruit in the diet, for these often
seem expensive materials in comparison with the amount
of energy and of building material which they contain, and
the poor are tempted to leave them entirely out of their
rations.
REFERENCES
Ohio Agri. Exp. Station (Wooster) Bulletin 201. "Mineral Ele-
ments in Nutrition."
Ohio Agri. Exp. Station (Wooster) Bulletin r 207. "The Balance
between Inorganic Acids and Bases in Animal Nutrition."
U. S. Dept. of Agriculture. Farmers' Bulletin No. 73, pp. 23-27.
"Losses in Cooking Vegetables."
U. S. Dept. of Agriculture. Office of Exp. Station Bulletin No. 43.
"Losses in Boiling Vegetables."
SETTING T
