12 MODERN BUTTER MAKING. 



ery man and the patron, the milk must either be 

 thawed or no sample taken from it on that day. 

 When badly frozen milk is warmed to 115° F. to 

 alloAv the mixing of it for sampling, it should be 

 mixed thoroughly by pouring several times, and 

 the sample should be taken quickly. The necessity 

 of sampling milk quickly after it is warmed suffi- 

 ciently to melt the churned butter fat, is due to the 

 fact that in partly churned or frozen milk the fat 

 when warmed enough to melt it, will easily float on 

 top of the milk by reason of its lower specitie 

 gravity. 



6. Care of composite milk samples. Be sure to 

 put a preservative tablet in each sample jar before 

 putting the sample of milk into it. Composite sam- 

 ples should be mixed daily and also whenever a new 

 sample of milk is added, by giving the sample jar 

 a few rotary motions. Thorough mixing is a great 

 aid toward getting good results at the time of test- 

 ing the milk. The sample jars should have tight 

 fitting covers and should be kept in a closed case 

 both in winter and summer. "When sample jars are 

 left open, especially in the hot summer time, cream 

 adhering to the sides of the jars will form a tough 

 layer — a mixture composed mostly of cream and 

 casein — which will cause trouble in sampling for 

 testing. (Farrington and Woll.*) 



7. Preparing composite samples for testing. Place 

 the sample jars in water of a temperature of 115 — 

 125° F. and allow them to remain in the water until 

 the milk is thoroughly warmed and the cream lique- 



* Farrington and Woll. Testing Milk and Its Products. Chap. II, 

 p. 23, 1904. 



