This section is from the book "Elements Of The Theory And Practice Of Cookery", by Mary E. Williams. Also available from Amazon: Elements Of The Theory And Practice Of Cookery; A Textbook Of Domestic Science For Use In Schools.
If you cannot be sure that the milk is from healthy cows and exceptionally clean, it should be pasteurized, boiled, or sterilized. What is the purpose of sterilization? of pasteurization? How would you pasteurize milk for family use? (See Home pasteurization, p. 97.) Milk pasteurized at 145° F. is about as nutritious and digestible for a baby as raw milk is, although there is reason to think that raw milk, if clean, has some advantages. Commercial pasteurization does not make milk safe for a baby. When his milk is to be pasteurized, this should be done after it has been modified and put into feeding-bottles.
Several makes of pasteurizers can be bought. The essentials are a circular rack made to hold feeding-bottles, a kettle or pail large enough to hold the rack, and a thermometer. The rack must hold at least as many bottles as the baby has feedings in twenty-four hours.1 With an improvised pasteurizer, a bath-towel or other thick cloth will be needed.
Directions for pasteurizing modified milk.2 - Set the bottles in the rack to fill them. Plug them with sterilized, but not absorbent, cotton. Place the rack in the kettle. Insert a thermometer in the neck of one bottle. Pour cold water into the kettle till it reaches above the level of the milk. Heat the water slowly and watch the thermometer. When it registers 145° F., remove the bottles. Change the thermometer from the milk to the water. Pour cold water into the kettle until the thermometer again registers 145° F. Put the bottles back and cover them with a clean bath-towel or other heavy cloth. Let them stand covered at least twenty minutes, and not more than thirty. Cool the bottles quickly. This may be done by running cold water into the kettle. Take out the cotton plugs, one at a time, instantly replacing each by a sterilized cork. Pack the bottles in ice or set them close to ice in the refrigerator.
1 In the absence of a rack, the bottles may stand on a tin pie-plate with a few holes punched in it. The plate is supported on blocks of wood.
2 Adapted from Circular 197. Bureau of Animal Industry. U. S. Dept. of Agriculture.
How does the method of pasteurizing in feeding-bottles differ from that of pasteurizing in milk-bottles? Why not cool the bottles by putting them on ice at once?
Boiled milk may be ordered for a very young baby, or for a baby with disordered digestion. It is not best, as a rule, to give it to a well baby for long at a time. If the milk is suspected of containing dirt or disease germs, it should be boiled as a precaution. The best method is to put the bottles of food in the pasteurizer, let the water come to a boil, and boil for forty-five minutes. Another way is to boil the modified milk in a saucepan for from one to two minutes, and pour at once into the feeding-bottles. Cool in running water, and place on ice. Use within twenty-four hours. How can you keep the bottles from breaking when the hot milk is poured into them ?