92 MAINE AGRICULTURAL EXPERIMENT STATION. 



strong ammonia to the contents of the bottle. After the con- 

 tents of the bottle have become cold, the usual amount of acid 

 should be added and the bottles shaken until the lumps of cheese 

 have entirely dissolved. The bottles are then placed in the 

 machine and whirled, the test being completed in the same 

 manner as with milk. To obtain the per cent of fat, the read- 

 ing should be multiplied by three. 



TESTING CONDENSED MILK. 



The estimation of fat in condensed milk is accomplished in 

 exactly the same way as with cream. As a rule, condensed 

 milks are so thick that it is impracticable to measure the test 

 sample directly with a pipette. This difficulty may be over- 

 come by carefully diluting the milk with a known volume of 

 water, making the analysis of this and correcting the result 

 for the quantity of water added. The best method is to weigh 

 the sample into a test bottle, taking about 9 grams, and after 

 adding about 9 cubic centimeters of water completing the test 

 in the same manner as with milk, the per cent of fat being 

 obtained by multiplying the reading by two. The results are 

 satisfactory. 



THE LACTOMETER AND FAT TEST FOR DETECTION OF 

 ADULTERATED MILK. 



The most common adulterations are the removing of cream 

 and the addition of water. By determining the fat and the 

 solids not fat, either or both of these adulterations are easily 

 detected. 



In many states legal standards for fat and solids not fat have 

 been established in order to protect the public against fraud. 

 In some states the required standard is 3 per cent fat, in others 

 3.5 per cent and solids not fat about 9 per cent. Milk from a 

 good sized herd varies but little from day to day. Milk from 

 a single cow may vary quite widely in fat., but from a herd will 

 seldom van* more than 0.2 or 0.3 per cent, and solids not fat 

 even less. 



It is rather difficult to fix any standard, so great is the varia- 

 tion in different animals, but it is very rare that the mixed 

 milk from a large herd at any season of the year will fall below 



