Chemical Analysis of Milk and lis Products. 233 



fat in the sample is obtained from the difference be- 

 tween this and the preceding weight. The gooch is 

 then carefully heated at a low red heat until a light 

 grayish ash is obtained; this operation is preferably 

 done in a muffle oven to avoid a loss of alkali chlorids. 

 The loss in weight gives the casein in the sample 

 weighed out, and the increase in the weight of the gooch 

 over that of the empty gooch with asbestos, gives the 

 ash (mainly salt) of the butter. The salt in the ash 

 may be dissolved out by hot water, and the chlorin 

 content of the solution determined by means of a stand- 

 ard silver-nitrate solution, using potassium chromate as 

 an indicator (278). 



272. Creamery methods of estimating water in 

 butter. A number of dilTerent methods have been pro- 

 posed of late years 

 for the rapid esti- 

 mation of water in 

 butter, the object 

 sought being to en- 

 able a buttermaker 

 to ascertain th-e 

 water content of his 

 butter without much 

 trouble or delay, 

 and by using such simple apparatus as he is likely to 

 have in the creamery or can easily procure at a low 

 price. The subject of controlling the per cent, of water 

 in butter has become more important than was earlier 

 the case, through the passage of the pure-food law, 

 and the promulgation of government food standards in 



Fig. 58a. 

 tor testing. 



Balance for weighing butter 



