MlLK -TESTING AND DAIRY RECORDS. 



9 



10. Fill with hot water to about the s-per-cent mark on the neck of the bottle. 



11. Finish hy whirling one minute. 



11'. Place the bottles in a hath of hot water (130 to 140 Fahr.) for five 



minutes, 



13. Kead from the highest to the lowest part of the fat column. 



14. Empty test-bottles and wash thoroughly. 



GETTING AN ACCURATE SAMPLE. 



Before making the test an accurate or representative sample should be taken. 



Too great care cannot be exercised at this step. .1 /'>/ /* /*/ n rulm- irliuh 



titix jHiinl /.s- orr/Voo/.v,/. if milk stands for even a very few minutes the cream 



Fig. 4. 

 Types of Babcock testers, in which the test-bottles are whirled. 



begins t;> rise, so that the top layer will contain more butter-fat than the rest of 

 the milk. A representative sample means one that is mixed by inuring and stirrim: 

 until it is uniform and homogeneous in richness. 



USE OF PRESERVATIVES. 



If for any reason the milk cannot be tested within a few hours after the sample 

 is taken, a preservative may l:e added to prevent souring or curdling. Tablets of 

 (orrosive sublimate, bichromate 'f potash, or some other ellicient preservative should 

 in' used. .Most <!' these are poisonous and must be used with caution. About tit'teen 

 drops of formalin makes a very satisfactory preservative when samples are not to 

 be held for more than two weeks. 



TAKING THE SAMPLE. 



The propei- temperature of the milk for testing i- 



from to 70 Fahr. At this temperature too 

 violent chemical reaction in mixing the milk and acid 

 is avoided, and enables one to obtain a clear, bright- 

 yellow fat column in the neck of the test-bottle. 



After thoroughly mixing the sample of milk to be 

 tested, insert the pipette in the sample and draw the 

 milk up to above the 17. t'.-c.c. mark. Place the fore- 

 finger over the upper end, then release the pivmv 

 slowly so as to allow the milk to run down to the 

 mark. The pipette will then hold the required amount. 

 and it can be transferred to the test -bottle. The test- 



I'i-. 5. This illustrates angle at 

 which the milk-bottle and the 



pipette should be held when trans- 

 bottle should be held in a slanting position < Fig. r, i to ferring milk to the bottle. 



allow the milk to run down slowly in the neck of the bottle and at the same time 



