FORTY-FIRST ANNUAL CONVENTION 323 



Condition of Cream Cans and Surroundings Where Cream' 

 IS Kept. Cream should be kept in cans or utensils that have pre- 

 viously been thoroughly cleaned and scalded. If cream is kept 

 where there are decaying or strong smelling vegetables, such as 

 are often kept in a cellar, it is likely to become more or less taint- 

 ed by absorbing the odors, so that the place where the cream is 

 kept should be properly ventilated and free from any objection- 

 able odors. 



Temperature. 



As soon as the milk or cream becomes contaminated by dust 

 or dirt getting into it or by passing through a dirty separator 

 large numbers of bacteria find it an excellent place to grow and 

 multiply. However, these bacteria grow more rapidly if the 

 milk or cream is warm than if it is cooled quickly. The ;' tem- 

 perature of fresh milk is most favorable to the rapid growth 

 of many species of bacteria, while they increase very slowly 

 if the temperature of the milk or cream is reduced to below 50 

 degrees F. That is why it is so important to cool milk or cream 

 promptly after milking or separating, and to keep it cooled if 

 it is to be kept sweet. The species of bacteria that causes milk 

 or cream to sour are commonly called the lactic-acid bacteria, 

 as they change the milk sugar to lactic acid, causing the milk or 

 cream to turn sour. These bacteria are very common and more 

 numerous than any other kind of bacteria, especially in summer, 

 when atmospheric conditions are most favorable for their rapid 

 growth; therefore it is almost impossible to keep them out of 

 milk or cream and the only way the farmer can keep his cream 

 in good sweet condition, even with the utmost care and cleanli- 

 ness in the previous handling of it, is by keeping it so well cooled 

 that these organisms will not grow. 



On the other hand cream will not keep in good condition 

 indefinitely even at the lower temperature, as there are organ- 

 isms that produce old and bitter flavors in cream and they grow 

 when the cream is too cold for it to sour. That is why old cream 

 is often bitter in winter time. 



