DAIRY PRODUCTS

201

Milk
100.0

Fat.....3.6

Milk

serum. .96.4

Glyceridee of
insoluble and
non-volatile
acids

Glycerides of
soluble and
volatile acids

Containing
nitrogen pro-
teids

Olein
Palmitin
Stearin
Myristin

Butin (trace) J aumB Fat....... 3.6

Butyrin
Caproin

Caprylin (trace)
Caprin (trace)

Casein......... 3.0

Albumin....... 0.6

Lactoglobulin
Galactin
Fibrin (trace)

Lactose.......

Citric acid.......................... 0.1 Solids not

Potassium oxide....... 0.175 f fat....... 9.1

Sodium oxide........... 0.070

Calcium oxide......... 0.140

Magnesium oxide...... 0.017

Ferric oxide........... 0.001

Sulphur trioxide....... 0.027

Phosphorus pentoxide.. 0.170

Chlorine.............. 0.100 .

Water.............................................. 87.3

3.3

0.3

3.8

4.5

Ash... 0.7

100.0

Preparation of Sample.—When milk is allowed to stand the fat
rises slowly to the top. Before the analysis is started it is
therefore necessary to mix the rnilk thoroughly by pouring from
one vessel to another several times, but without shaking vigor-
ously as air would thus be incorporated with the liquid anid there
would be also a coalescence of fat globules.

The following table will serve to indicate how far each deter-
mination must be carried before it can be stopped with safety:
TABLE XIV.—PROGRESS OF DETERMINATIONS

Determination

Stage after which work may be interrupted

Specific gravity......

Acidity.............

Total solids..........

Ash.................

Total nitrogen.......

Casein and albumin..

Lactose.............

Fat, paper coil.......

Rose-Gottlieb___

Babcock........

Cannot be delayed

Cannot be delayed

Evaporation of sample

Weighing sample

Addition of sulphuric acid

Filtration of proteins and addition of sulphuric acid

Addition of mercuric iodide or nitrate solution

Drying milk on paper coil

Extraction of the fat

Addition of sulphuric acid

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