MILK TESTS 451 



BvUer moisture-test (Cornell test). 



The apparatus used in the Cornell moisture-test is an alcohol lamp, 

 stand, asbestos sheet, hot-pan lifter, aluminum cup for holding the 

 sample, and a special moisture scale. The scale is especially adapted 

 for moisture work, but may be used as a cream scale in operating the 

 Babcock test. 



The scale has a tare weight for balancing the cup and a large and 

 small weight for weighing the sample and obtaining the percentage of 

 moisture. The beam has two rows of figures, which give readings 

 with the larger weight. The lower row gives readings in grams and 

 the upper row in percentages. The smaller weight gives readings in 

 grams when the weight is moved from 1 forward. Each notch repre- 

 sents .02 gram, the total value of the small scale being .2 gram. When 

 the small weight is moved from backward, each notch represents a 

 loss of .1 per cent of moisture when 20.2 grams of butter are used. The 

 small weight is intended to be used only in moisture work. In using 

 the scale for Babcock work, the small weight is not used, but is left at 

 rest on the figure 1. Then when the scales are balanced, the small 

 weight is negligible. Care must be taken not to let any draft of air, 

 as from an open window, strike the scales when in use, as they are so 

 sensitive that a very slight current of air would throw them out 

 of balance. The scales will give readings in percentages only when 

 20.2 grams of butter have been weighed, or, in other words, when 

 the large weight is on 20 (of the gram scale) and the small weight 

 is on zero. 



The cup used is of cast aluminum, and is durable and perfectly smooth. 

 The absence of creases or crevices allows it to be cleaned and dried 

 thoroughly. 



Taking the sample. — It is necessary that a representative sample be 

 taken for a moisture-test. If the butter is sold in tubs, the sample 

 should be taken from the tub with a butter-trier, after the butter has 

 been packed. It is best to take three drawings — one from near the 

 edge, one from the middle, and one half-way between the edge and 

 the middle. Some butter-makers test the butter as soon as it is 

 worked. This is a mistake, since considerable moisture is lost in 

 the process of printing and Dacking. 



