Pasteurized Milk
There is a certain degree of heat which, if maintained for a sufficient period of time, will destroy disease germs and certain other harmful germs which tend to spoil milk, while at the same time it is not high enough to cause the delicate flavour of raw milk to disappear. Bringing milk to this exact condition is called “pasteurizing” it. Into feeding bottles put the amount of milk that is to be used at one time. Plug them with sterilized (baked) cotton. Stand them on a rack in a cooker-pail, surrounded, to the depth of the milk, with warm water. Gradually raise the temperature till the milk in the bottles registers 150 degrees Fahrenheit. Cover the pail, and set it in a cooker for from twenty minutes to half an hour or more. Remove the bottles, cool quickly and keep the milk in a cold place, but not freezing, till needed. Do not remove the milk from the bottles if it is used for feeding infants. If used for adults do not remove it until it is to be used. Pasteurized milk will keep for a long time without souring, but is dangerous unless continuously kept very cold. Milk to be kept hot in a cooker for use in the night, should be put in while scalding hot, not merely pasteurized, since “any device for keeping milk [merely] warm should never be used.”[3]
[3] “Bacteria in Milk,” by L. A. Rogers. Yearbook of the Department of Agriculture, 1907, p. 194.