290 REPORT OF THE CHEMIST OF THE 
These results indicate that the light portions of butter contain 
more casein lactate than the deeper-colored portions. This casein 
lactate comes from retention of buttermilk. It is generally 
noticed that in working butter the liquid coming from the worker 
is turbid and milky when the buttermilk has not been removed, 
while it is more or less clear when the buttermilk has been prop- 
erly washed out of the granules before salting and working. 
The amount of water in mottled and unmottled butters.—The 
determination of water in mottled and unmottled butters gave 
the following results: 


Per cent of water in mottled butters. Per cent of water in unmottled butters. 
13.038 12.87 
18.00 10.52 
Le 10.50: 
15.35 12.00 
15.50 13.30 
Average.... 13.77 11.84 
The mottled butters vary greatly among themselves as well as 
the unmottled in respect to content of water. The larger amount 
of water in these mottled butters is the result of the retention of 
more buttermilk. 
Properties of proteid in butter and buttermilk.—The chief pro- 
teid of butter made from ripened cream is casein lactate. In 
fresh, sweet-cream butter, the chief proteid is calcium casein 
(milk-casein) with more or less free casein. On standing, these 
constituents may change, forming more largely a mixture of free 
casein and casein lactate and, if milk-sugar is present to form 
sufficient acid, casein lactate entirely. The proteids of fresh 
buttermilk are the same as those contained in the butter, and the 
exact kind and amount depend upon the amount of acid formed. 
In ordinary buttermilk, in which the proteid is casein lactate, we 
notice that the proteid exists in fine particles in suspension. 
When buttermilk is treated with salt so as to form a brine about 
equal to that of normal butter, the salt causes the proteid to con- 
dense or concentrate in a more or less solid mass. This effect of 
salt is readily shown in the accompanying illustration. In the 
samples containing 20 per ct. or more of salt, the proteid has 
separated in a marked manner. This same-action takes place 
