THE DISTRIBUTION OF MILK. 



61 



with the byre. It is unnecessary to say that such a practice is totally 

 against all rules of proper dairying. 



By the Pasteurizing of milk is understood a process of heating the milk, 

 for a short time, under the boiling point of water (between 56 and 80 .C.). 

 Milk is usually Pasteurized by placing it in the inside of a Pasteurizing 

 apparatus, and then heating up to 70 or 80 C., and subsequently cooling 

 to 12 C. It has been proved by experiment that the bacilli effecting lactic 

 fermentation are, for the most part, destroyed by a momentary exposure 

 of the milk to a temperature 

 of about 80 C., and the vita- 

 lity of the remaining bacilli, 

 along with the rest of the 

 lower micro-organisms present 

 in the milk, is so impaired 

 that their action is temporarily 

 stopped, and their develop- 

 ment checked for a time. If 

 this process be carefully car- 

 ried out, Pasteurized milk 

 does not exhibit, or exhibits 

 only to a very slight extent, 

 that peculiar unpleasant taste 

 possessed by boiled milk, 

 which is so disagreeable to 

 many people. We shall have 

 something to say in a subse- 

 quent chapter on the Pasteur- 

 izing of milk. 



For the purpose of effecting the rapid cooling of milk for general use, 

 the milk-cooler or refrigerator (fig. 22) constructed on the plan designed 

 by Lawrence is thoroughly to be recommended. It is able to treat per- 

 fectly from 200 to 1200 litres (44 to 263 gallons), of milk in an hour. 



It is believed in America that milk should be aired by means of special 

 apparatus, in order to free it from the so-called animal smell. In Europe 

 this custom is not general, and in Germany it is regarded as useless and 

 unnecessary. l 



27. The Distribution of Milk. In the moving about of milk, it 

 is necessary to protect it from rapid fermentation, violent shaking, 

 contamination, or adulteration. Milk in its warm condition may 

 only be moved short distances, such as, for example, from the byre 



iThis apparatus has been employed in some cases in Britain with advantage. Editors of 

 English Edition. 



Fig. 22. Lawrence Refrigerator. 



