82 MILK PRODUCTS 
The official methods of the A.O.A.C. for the 
analysis of butter are as follows: 
Preparation of the Sample.—lf large quantities 
of butter are to be sampled, a butter trier or 
sampler may be used. The portions thus drawn, 
about 500 grams, are to be perfectly melted in a 
closed vessel at as low a temperature as possible, 
and when melted the whole is to be shaken vio- 
lently for some minutes until the mass is homo- 
geneous and sufficiently solidified to prevent 
the separation of the water and fat. A portion 
is then poured into the vessel from which it is 
to be weighed for analysis, and should nearly or 
quite fill it. This sample should be kept in a 
cold place until analyzed. 
WaTER.—From 1.5 to 2.5 grams are dried to 
constant weight at the temperature of boiling 
water, in a dish with flat bottom, having a surface 
of at least 20 sq.cm. The use of clean dry sand 
or asbestos with the butter is admissible, and 
is necessary if a dish with round bottom be 
employed. 
Fat.—The dry butter from the water deter- 
mination is dissolved in the dish with absolute 
ether. The contents of the dish are then trans- 
ferred to a weighed Gooch crucible with the aid 
of a wash-bottle filled with the solvent, and are 
washed until free from fat. The crucible and 
