GIFT OF
157
U. S. DEPARTMENT OF AGRICULTURE.
FARMERS' BULLETIN No. 34.
.9 iar/
l /
MEATS: COMPOSITION AND COOKING.
BY
CHAS. D. WOODS,
OFFICE OF EXPERIMENT STATIONS.
[Corrected February 17, 1904.]
WASHINGTON:
GOVERNMENT PRINTING OFFICE.
1904.
-(4
LETTER OF TRANSMITTAL
U. S. DEPARTMENT OF AGRICULTURE,
OFFICE OF EXPERIMENT STATIONS,
Washington, D. C., October 12, 1895.
SIR: I have the honor to transmit herewith, for publication as a Farmers' Bulletin,
an article on the composition and cooking of meats, prepared under the immediate
direction of Prof. W. 0. Atwater, special agent in charge of nutrition investigations,
by Mr. Chas. D. Woods, vice-director of the Storrs (Conn.) Experiment Station, and
attached to this Office as an expert for nutrition investigations. This bulletin sum-
marizes the results of investigations regarding the nutritive value of different kinds
of meat, and points out some of the things which should be considered in the cooking
of meats for different purposes. The table appended to this article is based upon all
the available data regarding the composition and fuel value of American meats (exclu-
sive of fish), and is believed to be more complete than any similar table hitherto
published.
Respectfully,
A. C. TRUE,
Director.
Hon. J. STERLING MORTON,
Secretary.
CONTENTS.
Page.
Animal and vegetable foods compared
Structure of meats 4
Composition of meats 4
Refuse, as bone, skin, etc 5
Water 7
Fats 7
Nitrogenous constituents (protein) 10
Carbohydrates and ash
Texture (toughness) of meats 11
Flavor of meats 13
Digestibility of meats 13
The cooking of meats 14
Boiling 15
Stewing
Broths, soups, meat extracts 17
Roasting 18
Cute of meat 19
Cuts of beef 19
Cuts of veal 21
Cuts of lamb and mutton : 22
Cuts of pork 23
Composition and fuel value of meats 24
ILLUSTRATIONS.
FIG. x. Diagrams of cute of beef 20
2. Diagrams of cuts of veal 21
3. Diagrams of cuts of lamb and mutton 22
4. Diagrams of cuts of pork ,.,--. 23
34
MEATS: COMPOSITION AND COOKING.
ANIMAL AND VEGETABLE FOODS COMPARED.
The food of man can not be healthful and adequate unless it supplies
the proper amount of the different nutritive ingredients, or "nutrients."
Practical experience proves this, and experimental inquiry demonstrates
it as well. Just what the functions of the different foods are their
"nutritive value and cost" has been discussed in Bulletin No. 142 of
this series, and a knowledge of the facts there set forth is necessary to
a clear understanding of the present bulletin.
/ It is natural to divide foods into two classes animal food and vege-
table food. Not only is this division simple and convenient, as pointing
out the two great sources of man's food, but the classification is a true
one, for the difference between animal and vegetable food is very strik-
ing in appearance, composition, and value in the economy of life.
It is true that many of the chemical compounds which enter into the
composition of these two classes of food are either alike or quite simi-
lar; but in general the vegetable foods contain large amounts of carbo-
h}^drates such as sugar, starch, woody fiber, etc. while the animal
foods, and meat in particular, contain only small amounts of these
carbohydrates. As regards the fats and nitrogenous matters or "pro-
tein," the case is reversed; for vegetable foods have comparatively
little of these two classes of nutrients, while meats have relatively
very large amounts.
The value of meats as food, therefore, depends on the presence of two
classes of nutrients, protein and fat. The protein is essential for the
construction and maintenance of the body. Both protein and fat yield
muscular power and maintain the temperature. It is possible to com-
bine the fat of animal foods with the protein so as to meet the require-
ments of the body without waste, but the vegetable foods contain
nutrients more especially adapted for the production of energy.
284456 s
Another difference between animal and vegetable foods is in their
digestibility. The compounds contained in the animal foods are, of
course, very much like those of our bodies, and therefore need but little
change before they are ready for use. The vegetable compounds, on
the other hand, require much greater changes before they can be assimi-
lated. They are less readily and less completely digested than the
animal foods. This is due in part to the fact that the nutrients of
vegetable foods are often inclosed in cells with woody walls, which
resist the action of the digestive fluids, and in part to the action of the
woody fiber in irritating the lining of the intestine, and thus hastening
the food through the intestine before the digestive juices have time to
act thoroughly upon the food. Indeed, the presence of the woody fiber
frequently prevents the complete digestion and absorption not only of
the nutrients contained in the vegetable foods, but also of those con-
tained in the animal foods eaten at the same time.
STRUCTURE OF MEATS.
In the sense in which the word is here used, meat consists of the
muscular tissue, or lean, and the varying quantities of fat which are
found in the different parts, as between and within membranes and ten-
dons. Besides the fat ordinarily visible there is always present more
or less of fat in particles too small to be readily distinguished from the
lean which surrounds it. These particles can, however, be readily
obtained by chemical methods in quantities sufficient to be seen and
weighed.
The lean part of meat has practically the same final structure regard-
less of its kind and its muscular tissue. All muscular tissue is made
up of prism shaped bundles, which can be divided into smaller and
smaller bundles, until finally the muscle fibers or tubes are reached.
These irregular tubes are so small that they are 'invisible to the unaided
eye. They vary in diameter from ^ to ^^ of an inch.
These muscle fibers or tubes are held together in bundles by means
of connective tissue, and the invisible fat is stored between and inside
the different fibers and bundles of fibers. Each of the bundles of
muscle fibers, seen when a piece of meat is cut "across the grain," as
in a round steak, is made up of hundreds of the muscle tubes.
The envelope or wall of each tube is a very delicate, elastic mem-
brane, composed of nitrogenous material. The walls themselves are
quite permanent, but their contents are continual!} 7 undergoing change
and renewal.
COMPOSITION OF MEATS.
As regards composition, the meats found in the markets consist of
the lean or muscular tissue, connective tissue or gristle, fatty tissue,
34
5
blood vessels, nerves, bone, etc. No general statement can be made
with regard to the proportion in which these substances occur, as it is
found to vary greatly with the kind of animal, with different "cuts"
from the same animal, and with many other conditions.
REFUSE, AS BONE, SKIN", ETC.
Nearly all meats bought and sold in the markets contain some por-
tions not suitable for eating, which may properly be designated as
refuse. Some of these, as bone, contain some nutriment, and may be
utilized to a greater or less extent in making soups, and perhaps in
some other ways; but for the most part they are thrown away.
It is important to distinguish between refuse and "waste." As the
term is ordinarily used, any portion considered unsuitable for eating
would be designated as refuse. At another time or under other con-
ditions, it might be desirable to use for food the portion which was
before considered useless. Such portions, therefore, are not refuse in
the proper meaning of the term. They are waste. Some parts of
meat, however, from their lack of nutrients or from the impossibility
of preparing them for food, are and always will be useless, and these
portions we may properly call refuse. As population increases there
is, however, an increasing tendency to utilize portions of meats which
have hitherto been thrown away. If our classification is to be a true
one, therefore, we must narrow the use of the term "refuse" from its
generally too-broad application and must cover much of its popular
meaning by the term "waste." The skin of fish and poultry, "rind"
of pork, case of sausages, etc., are illustrations of materials which
might by one person be classed as refuse and by another be consid-
ered edible and thus be classed as waste if they were rejected at the
table.
In ordinary meats the chief refuse is bone. The percentage of bone
varies so greatly that no precise statement can be made. In many
species of fish, bone constitutes more than one-half the dressed weight.
In some cuts of meat, on the other hand, notably the round of beef,
slice of ham, and similar cuts in other animals, there may not be more
than 2 or 3 per cent of bone, and in still other cuts, as shoulder clod,
there will be no bone at all.
In general, the younger the animal the larger the relative proportion
of bone, and with increase in fatness there is a relative decrease in the
amount of bone.
The following diagram shows graphically the variations in the refuse,
chiefly bone, in different kinds and cuts of meats.
The smallest and largest percentages of refuse found in different kinds and cuts of ineats,
Kind of meat.
Percent.
Comparative scale.
Beef:
Side
j from 12
|
Sirloin
Ito 21
ffrom 4
:
Round
tto 26
ffrom 4
'
BB
tto 11
Shoulder and clod..
ffrom 5
tto 28
mmm
Veal:
Side
(from 19
I^MUHOMM
Chops
Ito 25
ffrom 14
MBnoamHBMMM
Cutlet
Ito 20
rfrom 13
Mutton:
Side
ffrom 13
_
\to 23
Chops
ffrom 11
tto 20
Lee
ffrom 12
tto 24
.*
Pork:
Chops
ffrom 12
1
Ito 24
piYinVed hftTn
ffrom 8
mttmt
Halibut steak
tto 14
ffrom 11
=r
Cod
tto 23
ffrom 26
mmmm,
^i
\to 34
Mnr>Vral
ffrom 34
(to 58
Ito 59
tto 88
ffrom 40
tto 45
ffrom 44
\to 61
(6)
WATER.
Meats contain large and varying amounts of water. For the pur-
poses of mastication, swallowing, etc., of course this is better than if
the meat were dry; but the water contained in flesh has no greater
value as food than other water. From this it follows that the greater
the amount of water in a given weight of food the less is its relative
nutritive value, for it will contain a less quantity of nutritive material.
Fish and oysters have relatively more water than most other meats.
In general, the greater the amount of fat in a given cut the less is the
amount of water. For instance, a lean cut of beef may have 75 per
cent of water, while a fat cut from the same animal may not contain
more than 50 per cent.
The diagram on page 8 illustrates the variations in the quantity of
water in the edible portions of different kinds and cuts of meats.
FATS.
All meats contain some fat, partly stored in quantities so large as to
be readily seen, and partly distributed in such small particles that it is
only by chemical means that it can be obtained in quantities sufficient
to be appreciated. In the flesh of some animals, as cod and other
white-meated fish, and in chicken (} T oung fowl), rabbit, and veal, there
is little or no visible fat. In a very fat ox, on the other hand, one-
fourth of the weight of meat may be visible fat, and, in the case of fat
hogs, more than half the weight may be fat. No flesh is so lean as not
to contain at least minute portions of fat. Very lean flesh, as dried
beef, may not have more than 3 per cent of fat, while fat pork may
contain more than 90 per cent.
Fat is a valuable constituent of food. It is used in the body to form
fatty tissue and is consumed as fuel, thus serving to maintain the
animal temperature and to yield energy in the form of muscular and
other power. It is the most concentrated form in which the fuel con-
stituents of food are found. Its fuel value is two and one-fourth times
that of protein or the carbohydrates. In other words, 1 pound of fat
yields as much heat when burned as 2i pounds of carbohydrates, such
as starch, sugar, etc. The fat of animal foods might be so supplied
that, together with animal protein, all the needs of the body could be
met. The fuel constituents of vegetable foods are, however, better
adapted to furnish a large part of the energy required by the body.
The diagram on page 9 illustrates the variations in the percentage
of fats in the edible portions of different kinds and cuts of meats.
84
The smallest and largest percentages of water found in the edible portion of different
kinds and cuts of meat.
Kind of meat.
Per cent.
Comparative scale.
Beef:
Side
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
\to
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
/from
tto
48
72
51
75
57
75
61
74
62
75
69
74
61
75
67
77
39
59
31
56
52
68
38
60
22
57
12
70
79
81
84
64
Sirloin
Round
Hind shank
Shoulderandclod
Veal:
Side
Chops
Cutlet
Mutton:
Side
Chops . .
Leg
Pork:
Chops
Smoked ham
Fat, salt .
__
Halibut steak
Cod
Mackerel
79
65
74
82
Shad
Oysters
Long clams
91
85
86
79
Lobster
(8)
The smallest and largest percentages of fat in the edible portion of different kinds and
cuts of meat.
Kind of meat.
Per cent.
Comparative scale.
Beef:
Side
("from 6
Sirloin
\to 36
/from 9
_
Round
/from 3
.
Hind shank
/from 4
(to 19
m
Shoulder clod
Veal:
Side
/from 1
tto 22
/from 6
3
Chops
\to 10
/from 5
Cutlet
\to 19
/from 1
i
Mutton:
Side
\to 12
x
/from 23
Chops
ffrom 26
Itn SQ
Leg
/from 12
Ito 30
,___
Pork:
Chops
ffrom 19
Smoked ham
/from 17
Ito 57
Fat, salt
/from 83
Halibut steak
/from 2
Cod
\to 10
/from . 3
Mackerel
(to .5
/from 2
i
Shad
\to 16
/from 7
^MHMH
Oysters
\to 14
/from .6
Long clams
\to 2
/from 1
I
Lobster
\to 1
/from 3
v
tto 2
(9)
30398 No. 3408 2
10
NITROGENOUS CONSTITUENTS (PROTEIN).
There are a great many kinds of nitrogenous compounds in flesh,
and an almost hopeless confusion exists in their classification and in
the names assigned to the various classes by different chemists.
Chemists are quite generally agreed, however, in designating the total
nitrogenous substance as protein. These compounds containing nitro-
gen may be arranged in the following three groups or classes:
PROTEIN:
Albuminoids, as albumen (white of eggs); casein (curd) of milk; myosin, the
basis of muscle (lean meat) ; gluten of wheat, etc.
Gelatinoids, as collogen of tendons and ossein of bones, which yield gelatin or
glue, etc.
Nitrogenous extractives. Meats and fish contain very small quantities of so-called
extractives. They include creatin and allied compounds, sometimes called
meat bases, and are the chief ingredients of beef tea and meat extract.
The nitrogenous compounds of meats are made up chiefly of albumi-
noids and gelatinoids. The albuminoids are so called because they
resemble albumen or white of egg in their properties, and the gelati-
noid substances are so named because of their similarity to gelatin.
They are easily changed into gelatin by the action of hot water or
steam, as in the manufacture of gelatin and glue from bones.
The value of meats as food is chiefly due to the nitrogenous com-
pounds which they contain, and of these the most valuable are the
albuminoids. This is due to the fact that they are very similar in com-
position to the nitrogenous compounds of the body, and are therefore
easily digested and assimilated. Experiments with sheep, swine, dogs,
and other animals seem to show that feeding rich, nitrogenous foods
considerably increases the percentage of albuminoids in the flesh.
Very different views have been held at different times as to the
value of gelatin as a food. At one time it was considered nearly as
valuable as the albuminoids themselves; but later, from the investiga-
tions of the "French Gelatin Commission," it fell into disrepute and
was held to have almost no food value. Later and better conducted
experiments, however, have demonstrated that gelatin, when combined
with albuminoids and extractives, has a very considerable nutritive
value and serves to economize the albuminoids.
The last class, known as nitrogenous extractives, or meat bases, are
so called because of the ease with which they may be dissolved out
(extracted) by water. They are formed by the decomposition (cleavage)
of albuminoids and probably gelatinoids. They consist largely of
creatin and creatinin, substances which somewhat resemble thein and
caffein, the active principles of tea and coffee. They are of little
value as food, but they give flavor to meats, and are therefore of great
importance. They will be referred to again when we come to consider
the flavor of meats, soups, and meat extracts.
The lean of meat has, in round numbers, about 20 per cent of pro-
tein, or, weight for weight, about five times as much as milk. The flesh
at
II
of fowls, especially wild fowl, has on the average more protein than
beef, and the flesh of fish has less.
While protein is the most important and valuable ingredient of food,
lean flesh is, nevertheless, a one-sided diet, and to make a well-balanced
ration for man the addition of foods containing carbon, such as fat,
starches, sugar, etc., is necessary.
The diagram on page 12 illustrates the variations in protein in the
edible portions of different kinds and cuts of meats.
CARBOHYDRATES AND ASH.
Although carbohydrates occur in considerable quantities in other
foods, flesh contains but a small amount only a fraction of 1 per
cent and that chiefly in the form of glycogen, or muscle sugar. In
some of the organs, notably the liver, there are considerable quantities
of glycogen.
Meats also contain more or less of mineral matters (ash) which have
value as food. The most important of these are the phosphates of
potash, lime, and magnesia. These are used chiefly in the formation
of bone.
TEXTURE (TOUGHNESS) OF MEATS.
Whether meats are tough or tender depends upon two things the
character of the walls of the muscle tubes and the character of the
connective tissues which bind the tubes and muscles together. In
young and well-nourished animals the tube walls are thin and delicate,
and the connective tissue is small in amount. As the animals grow
older, or are made to work (and this is particularly true in the case of
poorly nourished animals), the walls of the muscle tubes and the con-
nective tissues become thick and hard. This is the reason why the
flesh of young, well-fed animals is tender and easily masticated, while
the flesh of old, hard-worked, or poorly fed animals is often so tough
that prolonged boiling, or roasting, seems to have but little effect on it.
After slaughtering, meats undergo marked changes in texture. These
changes can be grouped under three classes or stages. In the first
stage, when the meat is just slaughtered, the flesh is soft, juicy, and quite
tender. In the next stage the flesh stiffens and the meat becomes
hard and tough. This condition is known as rigor mortis and continues
until the third stage, when the first changes of decomposition set in.
In hot climates the meat is commonly eaten in either the first or second
stage. In cold climates it is seldom eaten before the second stage, and
generally, in order to lessen the toughness, it is allowed to enter the
third stage, when it becomes soft and tender, and acquires added flavor.
The softening is due in part to the formation of lactic acid, which acts
upon the connective tissue. The same effect may be produced, though
more rapidly, by macerating the meat with weak vinegar. Meat is
sometimes made tender by cutting the flesh into thin slices and pound-
ing it across the cut ends until the fibers are broken.
34
The smallest and
largest percentages of protein in the edible portion of different kinds
and cuts of meats.
Kind of meat.
Perc
ent. Comparative scale.
Beef:
Side
("from
15 p
Sirloin
\to
ffrom
10 "
Round
\to
/from
Hind shank
(to
/from
"
Shoulder clod
Veal:
Side
[to
/from
\to
/from
s
Chops
(to
/from
"1
Cutlet
(to
ffrom
"1
Mutton:
Side
\to
ffrom
Chops
\to
/from
Leg
\to
[from
Pork:
Chops
(.10
/from
Smoked ham
/from
\to
Fat salt
ffrom
1 i
\to
Halibut steak
Cod . ..
\to
/from
19 p^" '
Mackerel
\to
ffrom
