662 ANNUAL REPORT OF THE Oil. Duo. 



QV; ouly half throu<ili the cheese. For inspection purposes, the rlud 

 maj be rejected but for investigations , where the absolute quan- 

 tity of fat in the cheese is required, the rind should be iiicluded 

 in the sample. It is well, when admissible, to take two or three 

 plugs on dift'erent sides of the cheese and, after splitting them 

 lengthwise with a sharp knife, take portions of each for the test. 



For the estimation of fat in cheese, about 5 grams should be 

 carefully weighed and transferred as completely as possible to a 

 test bottle. From 12 to 15 c. c. of hot water are then added and 

 the bottle shaken at intervals, keeping it warm, until the cheese 

 has become softesied ,and converted into a creamy emulsion. This 

 may be greatly facilitated by the addition of a few drops of strong 

 ammonia to the contents of the bottle. After the contents of the 

 bottles have become cold the usual amount of acid should be added 

 and the bottles shaken until the lumps of cheese have entirely dis- 

 solved. The bottles are then placed in the machine and whirled, 

 the test being completed in the same manner as with milk. To 

 cbtain the per ce«iL of fat, the reading should be multiplied by IS 

 and divided hj the weight, in grams, of cheese taken. 



89. Testing Composite Samples at Creameries and Cheese Factories. 

 Provide a pint or quart fruit-jar for each patron, on which shall 

 be a name or number distinguishing each. In each jar place about 

 as much powdered potassium bichromate as can be held in the 

 empty shell of a 32-oz. cartridge or about as much as one can 

 place on a silver dime; this will keep the milk from souring. 

 Provide a small tin cylinder holding one or two ounces of milk 

 when filled to the brim, provided with a handle of convenient length. 

 When a patron delivers his milk, pour it into the weighing can 

 from a height sufScient to secure thorough mixing of the whole, 

 and immediately, before weighing, insert the small tin cylinder, 

 fill with milk to the brim and transfer to the fruit jar set aside 

 for that patron's milk. In case this pouring does not mix the milk 

 thoroughly ,then stir the milk in the weighing can with a long- 

 handled dipper. This is repeated each day for six or seven days 

 with the milk of each patron. Whenever a fresh sample of milk 

 is placed in the jar, it should be mixed with the milk already in 

 the jar by giving the jar a rotary motion. If this is not done, the 

 cream which separates is liable to adhere tenaciously to the sides 

 of the jar and make it difficult to take an accurate sample w^hen 

 the test is made. Whenever an additional sample of milk is put 

 into a jar, it should be immediately and tightly closed. The jars 

 should be kept in a cool place during the week. If kept too warm, 

 the cream becomes hard and cannot readily be mixed back into 

 the milk, which will cause law results in the test. 



