THK MOJONNIKR TEST 369 



cross. Replace pipette and weigh again. Difference in weight 

 gives weight of sample. Repeat until all samples are run into 

 proper flasks, and into weighed solids dishes if solids are deter- 

 mined along with the fat. 



For fat in Sweetened Condensed Milk use a five-gram 

 sample. The five-gram pipette delivers approximately five 

 grams between the five-gram mark and the base of the bowl of 

 the pipette. 



Some operators prefer to mix 200 grams of sweetened con- 

 densed milk with 200 grams of water, weighing these carefully 

 upon a Harvard trip scale sensitive to .1 gram. In this case care 

 must be exercised to obtain the exact weight of both milk and 

 water and to stir these thoroughly with glass or metal rod before 

 taking sample. A tall tumbler, a one-pound bottle or a quart 

 cup make good containers in which to make, mixture. A ten- 

 g-ram sample of this mixture is used. This is best weighed out 

 by using two five-gram pipettes on weighing cross. 



For total solids weigh out ^ (.5000) to ^4 (.7500) gram of 

 this mixture. If the undiluted milk is used take as nearly (.2500) 

 gram as possible. 



For regular 8 per cent plain bulk condensed milk use same 

 size samples and treat same as evaporated milk. For 12 per cent 

 superheated condensed milk mix 100 grams milk with 300 grams 

 water upon Harvard trip scale. Weigh ten-gram sample of this 

 mixture into flask for fat and a two-gram sample into solids 

 dish for solids. Multiply percentages obtained by four for cor- 

 rect percentages, when a 1 to 4 dilution is made. 



FRESH MILK, SKIM MILK, WHEY, BUTTERMILK. 

 Butter Fat Determination. 



(1) Use the ten-gram pipettes for measuring out ten grams 

 of milk into cleaned but not necessarily dried Mojonnier extrac- 

 tion flask. Use only ten-gram pipettes furnished with tester 

 and do not use 10 c.c. pipettes. The pipette is graduated to 

 deliver ten grams of milk after allowing all milk to run out 

 and letting it drain for fifteen seconds longer, then blowing 

 gently to remove last drop. .The pipette must be perfectly clean 

 and dry before being used. Wash frequently with sulphuric acid, 

 water, alcohol and ether to insure having a clean pipette. 



