1. Whole milk. It must not be altered by the removal of cream nor the addition of such preservatives as salicylic acid, formaldehyde or boracic acid.
All of this means that the milk must come from a herd of healthy, tuberculin-tested cows. The milk from a single cow may vary markedly from day to day but that from several cows is nearly constant. The stables and the cows must be kept clean, the udders carefully washed before each milking; the milkers themselves must wear freshly washed clothing, scrub their hands thoroughly and milk into sterile receptacles; the milk must be immediately covered and cooled to a temperature of 45° F. or 50° F. and kept there.
Milk produced under such conditions is usually described as “certified milk” and is often prescribed as infant food without being pasteurized or sterilized. But if there is any doubt about the source of the milk and the method of its handling, it should be strained into a clean receptacle through filter paper or a thick layer of absorbent cotton and subsequently boiled or pasteurized.
Whether certified or not, the milk should invariably be placed in the refrigerator, or some other place which has a temperature of 50° F., as soon as it is received, and it must be kept cool and clean.
Keeping milk cool means keeping it at a temperature of 50° F. Keeping it clean implies cleanliness not alone of the milk itself but of your hands and the utensils that you use as well as the destruction of disease germs by pasteurization or sterilization. Among the germs which are likely to be present in infected milk are those that cause diarrhea, sore throats, typhoid fever, diphtheria and scarlet fever.
When the doctor makes out the formula for the baby’s milk, he will adjust the proportions of the different ingredients to the baby’s immediate needs and digestive powers. But his careful estimations will be set at naught unless you are absolutely accurate in preparing and giving the milk. Your invariable responsibility in connection with the baby’s milk, therefore, is to keep it cool and clean and be accurate.
You will appreciate the necessity for modifying cows’ milk before giving it to your baby if you will note the differences between mother’s milk and cows’ milk as indicated by the following table and consider, too, why Nature has made these differences:
| Mother’s Milk | Cows’ Milk | |||||||
|---|---|---|---|---|---|---|---|---|
| Fats | 3.5 | to | 4. | per cent | 3.5 | to | 4. | per cent |
| Sugar | 6.5 | to | 7.5 | per cent | 4.5 | to | 4.75 | per cent |
| Proteins | 1. | to | 1.5 | per cent | 3.5 | to | 4. | per cent |
| Salts | .2 | per cent | .7 | to | .75 | per cent | ||
| Water | 87. | to | 88. | per cent | 87. | per cent | ||
The various tissues of the body and the bony skeleton are built by the proteins and salt. Accordingly Nature supplies these in greater abundance to the baby calf, who grows so fast as to double his birth weight in about forty-seven days, than to the baby boy who scarcely doubles his birth weight within 180 days. The calf begins life with a physical need for the large amount of proteins and salts which are present in cows’ milk and with digestive organs that can cope with them, but the baby needs less, can digest less and, therefore, should be given less. There are of course, other and finer differences between the two milks and an attempt is sometimes make to meet these. For example, mother’s milk is slightly alkaline and cows’ milk slightly acid and the curd of cows’ milk is larger, tougher and harder to digest than that formed by mother’s milk. Some doctors add lime water to cows’ milk, before giving it to the baby, to make it alkaline and have the curd made softer, finer and more digestible by boiling.
Articles Needed in Preparing the Baby’s Food. A complete equipment for preparing and giving the baby’s milk should be assembled, kept in a clean place, separate from utensils in general use, and never put to any other service. A satisfactory outfit for this purpose comprises the following articles: