92 



Testing Milk and Its Products. 



handled ; it has recently been made of heavier glass and 

 this form is to be highly recommended. 1 



100. The double-sized skim milk bottle, which was the 

 first one recommended for the testing of skim milk, is of no 

 particular value. It is difficult to obtain a thorough mixture of 

 the milk and the acid in these bottles, and the tests invariably 

 come too low, more so than with the regular Babcock bottles or 

 the double-necked skim milk bottles, for reasons 

 that are readily seen. 



101. Buttermilk and whey. The 

 testing of buttermilk or whey by the 

 Babcock test offers no special difficul- 

 ties, and what has been said in regard 

 to tests of separator skim milk is equally 

 true in case of these by-products. Whey 

 contains only a small quantity of solids 

 not fat, viz., less than 7 per cent. (27), 

 and the mixing with acid and the solu- 

 tion of the whey solids therein is there- 

 fore readily accomplished; the acid so- 

 lution is of a light reddish color, turn- 

 ing black but very slowly. 



TOiz Riitt^r "Rntfpr i<a not sn pasi'lv^ - 88 ' Tbe Wagner 



102. Duner. cutter is LOI so easily sklm mllk Bottle, 

 tested as other dairy products, both because of the dif- 

 ficulties in obtaining a fair sample, and on account of 

 the high percentage of fat it contains. Butter is a me- 

 chanical mixture of water, curd, and salt, with butter- 

 fat; and the water or brine is so easily pressed out that 

 great care must be taken to get the same amount of 



1 A double-necked copper test bottle with a detachable graduated 

 glass neck was designed and tried by one of us a few years ago, but It 

 was not found to possess any special advantages over the glass bottle. 



WAGNERS, 

 OUBLE BOR' 

 KiMMED MILI| 



TESTING BOTTU 



