TREATMENT OF MILK FOR MARKET 159 



cream. Its consistency may be restored by adding a little of 

 a material called "viscogen." x This is made by adding a strong 

 solution of cane sugar to freshly slacked lime and allowing the 

 mixture to stand until the upper part of the mixture is clear. 

 This clear liquid is poured off and added to the cream in propor- 

 tions of i part to loo or 150 parts of cream. This restores the 

 consistency to the cream, but since it is an addition of a foreign 

 substance its use is illegal. 



The effect of pasteurization upon the fat of milk proves a 

 detriment in another way, since it interferes with the ready 

 separation of the fat from milk. When the fat of normal milk 

 is examined under the microscope the globules are found to 

 be bunched together in little groups; but the fat globules 

 of pasteurized milk are nearly separate from each other. 

 This interferes with the cream rising as usual and there is no 

 sharp line separating the cream and the milk after standing. 

 This does not interfere with the use of the milk, but if it is 

 desired to separate the cream from the milk it cannot be done 

 so easily as with raw milk. In the feeding of infants it is some- 

 times desired to separate the top third for separate use, this 

 third containing the most fat. Pasteurized milk cannot be 

 readily treated in this way, so that the absence of a "cream line" 

 is a real disadvantage. 



TYPES OF MARKET MILK 



The various suggestions for improving the quality of milk 

 above given will, when followed out, produce a type of milk far 

 different from that which has been common in our markets in 

 past years. But it is impossible to carry out these various direc- 

 tions without expense. It is impossible to produce a high grade 

 of milk for a low price. To obtain a type of milk that is being 

 demanded by health officers will involve an expenditure which 

 will evidently raise the price of milk. As soon as the public is 



1 Babcock and Russell. Bui. 44 Wis. Exper. Sta., 1896. 



