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DAIRY LABORATORY GUIDE 



EXERCISE 9 



TEMPERATURE IN READING THE TESTS 



Object : To determine the influence of varying temper- 

 atures upon the accuracy of the test in reading the fat column 

 of milk and cream. 



Apparatus : Samples of milk and cream, two whole-milk 

 bottles, two cream bottles, thermometer, and testing outfit. 



Steps: 1. Prepare the samples and complete the tests 

 as usual. 



2. Read immediately after stopping the tester and record 

 the temperature by inserting a thermometer into the neck of 

 one of the cream bottles until the mercury bulb is immersed 

 in the butter-fat. Allow it to remain in place throughout the 

 exercise and use this reading for all of the other bottles. 



3. Reread the tests at intervals of three and five minutes 

 when left standing. 



4. Set the test bottles into a waterbath at 120F. for 

 two minutes; then reread and record all data. 



5. Set the test bottles into a waterbath at 70F. for 

 two minutes; reread. 



Data: 



