CLEANEST TYPE OF MILK

Chronicle (Levin), 13 April 1946, Page 3

CLEANEST TYPE OF MILK

Milk drawn without contamination from an absoiutely liealthy cow sliould by its nature be quite free froiu. bacleria of any ldud, states the New Zcaland Dairy Ixesearcli Institute, in the second "of its new ciroulars just issued to dairy factories. Many people engaged in the industry are under the impression that a milk sample which has been drawn from the cow with the ntmost care to avoid contamination sliould, 011 keeping, undergo "clean" souring. They imagine that the desirable milk-souring bacteria either arise spontaneously in milk or arc normal inhabitants of milk. This is a fallacy. While milk when drawn sliould be absoiutely free from bacteria, in practice very few cows have bae-teria-free udders for long. Consequent]y, the milk does contain, when drawn, a few bacteria; but these are not true millc-souring bacteria. All milk-souring bacteria get into milk after it leaves the cow's udder. The fact that souring is the most usual happening when milk is kept for some time' is explained by the souring bacteria being the most active growers of the mixture of bacteria whieh nsually gets into milk. Actually, the greater the precautions taken in drawing a semple of milk from a healthy cow the more likely is the milk to "go badn on keeping, instead of souring; because the few bacteria which do gain access may not inelude any souring types, and the "putref active'^ types go hhead in the absence of competition. The "cleanest" milk, therefore, is not the milk whieh gives a "clean" sour after a day or two, but the milk -which keeps sweet for two or even three days and then "goes bad."