Farm Dairying 257 



366. Judging Butter. Butter is now judged by a 

 scale of points just as the breeds of live stock and crops 

 are. The points of most importance are (1) flavor, 

 (2) texture, (3) color, (4) salt, and (5) package. Varia- 

 tions in flavor are due to several causes, such as breed 

 of cows, individuality of cow, nature of feed, acidity of 

 cream and kind of bacteria in the cream. Variations 

 in texture are due chiefly to the nature of the feed and 

 the temperature at which the cream ripens, and, also, 

 the churning temperature, as discussed above. 



367. Pasteurization. One way of keeping milk 

 longer than could be done under natural conditions, 

 consists in heating to a temperature of 160 Fahr. 

 and then rapidly cooling. This method' of treating milk 

 is known as Pasteurization, and takes its name after 

 Pasteur, the great French bacteriologist. The object 

 of heating and cooling is to destroy the majority of 

 bacteria present, and prevent the others which are not 

 affected at that temperature, from becoming active. 

 The temperature given above is deemed sufficient to 

 destroy all, at least all disease-producing, germs and is 

 not high enough to affect the flavor of the milk. 



368. Clarification. We have just observed the 

 practice of freeing milk from bacteria in order to make 

 it "keep" longer. Now let us note the practice employed 

 in freeing the milk from undesirable foreign matter. 

 It matters not how careful the milker is in doing his 

 work, there is always more or less foreign matter, which 

 passes through a "strainer." This substance may be 

 separated from the milk by centrifugal force. The 

 process is known as clarification, and the machine 

 used is known as a clarifier. The machine is built on 

 precisely the same plan as a cream separator. 



