We mention these experiments as a warning against placing too great reliance on the caloric theory or the relation of nutrients in making up food rations. We have yet much to learn and the good housewife trying to cook according to scientific rules will do well not to neglect the palatability of the food, but to watch the “instinct” which causes the child or the adult to reject or approve of, and enjoy, the food, which in most cases is a better guide than calories or protein contents, or the ration between the various groups of nutrients.
CARE OF MILK IN THE HOME
If received fresh and warm from the cow, milk should at once be strained through absorbent cotton or several thicknesses of cheese-cloth into wide-mouthed bottles or glass jars and placed in running water or ice water to cool as quickly as possible. If obtained from the milkman it may be left in the bottle in which it is received. The practice of delivering milk “loose,” dipping it from the wagon, should not be permitted, and is fast being abolished. Public safety demands that it should be bottled on the farm or in the creamery or milk station under sanitary conditions.
Keep the Milk Cool.—If the milk when delivered at the house is not cold enough to keep sweet as long as desired, it should, we repeat, be placed in ice water or cold running water until thoroughly cooled. Even if the air is cold, in the ice box, for instance, the milk cannot be cooled quickly enough without water. After it has been cooled in water it may be put in the ice box. In most ice boxes the temperature is allowed to rise higher than is generally supposed, and it is better to keep the milk bottle next to the ice than in the food compartments.
A clean ice box
Milk and cream easily absorb flavors from the air and should not be kept in open vessels next to other food. Any housekeeper knows how quickly milk or cream will be tainted by standing in the same compartment with onions or muskmelons; if the bottle is not covered, milk may also be contaminated by other less noticeable but more harmful vapors from nearby products. Let the milkman furnish you with some extra milk bottle caps, or cover your milk bottle with an inverted tumbler.
As has been shown in previous chapters, milk is a favorable soil for all sorts of germs and bacteria to grow in. It must therefore be kept from contamination with the utmost care, and everything that comes in contact with it must be scrupulously clean.
Top-Milk.—When the milk has been standing at rest three or four hours, the top-milk will be considerably richer than the rest. If such rich milk is wanted for any particular purpose it may be poured off, to be eaten with cereals, berries, etc. In twelve hours most of the cream will rise and may be skimmed off, although thirty-six or even forty-eight hours may be required to get all that can be obtained by setting. The half-skimmed milk left when the top-milk has been removed after 3 to 6 hours’ setting will still contain 2% or more of butter-fat and is very good for drinking; even the skim milk from which the cream has been taken after 12 hours’ setting is still an excellent beverage, provided it is sweet. Perfectly skimmed, almost entirely fatless, milk may be used in various ways in cooking, to make up for lack of protein in many other food products. But care must be taken that it is pure and sweet, or rather, its condition, sweet or sour, must be under the perfect control of the housekeeper. If a sample of milk will stand scalding or even boiling without curdling, it is usually fresh and in good condition for any use. On the other hand, if it curdles by scalding, it is beyond control and it may or may not make good sour milk, depending on the bacteria working in it.