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DAIRY LABORATORY GUIDE 



EXERCISE 11 



. OPEN AND COVERED CONTAINERS FOR DAIRY PRODUCTS 



Object: To determine the effects upon quality of 

 keeping milk and cream in open and covered containers. 



Apparatus: Samples of milk and cream, jars, thermom- 

 eter, acid tester, and Babcock testing outfit. 



Steps: 1. Obtain two pints of milk warm from the 

 cow and two pints of cream immediately after separating. 



2. Arrange the bottles in sets of two, with milk in bottles 

 1 and cream in bottles 2. Leave one set open and cover 

 the second set with tight-fitting covers. 



3. Set the samples aside at ordinary room temperature 

 and examine at intervals for odor, flavor, and acidity. 



4. Secure two Mason jars or two milk cans with tight-fit- 

 ting covers. Wash them perfectly clean by ordinary methods 

 and then cover one tightly and leave the other open. Exam- 

 ine them after a few hours and note the odor when removing 

 the cover. 



Data: 



