1 90 DAIRY TECHNOLOGY 



We have previously noted that the conditions of the milk 

 and cream supply in many localities are far from ideal. 

 Since milk and cream are the main constituents of ice 

 cream, this latter product cannot be of any better quahty 

 than the materials of which it is made. However, all 

 methods of improving milk and cream are just as applicable 

 to the ice-cream industry as to city milk supply. 



Investigations of conditions in Washington, D. C, re- 

 ported in Bulletin 56 of the Hygienic Laboratory, show 

 that, in 1907, in 130 samples of cream examined, the average 

 number of bacteria per cubic centimeter was 12,130,080. 

 At the same time, 381 samples of milk were subjected to 

 a bacteriological examination and the average nimiber of 

 organisms per cubic centimeter was 3,415,533. Samples 

 of ice cream at the same time contained from 100,000 to 

 400,000,000 bacteria per cubic centimeter. 



Dr. George W. Stiles of Washington, D. C, investigated 

 the bacterial flora of ice cream in cold storage, and secured 

 the following results: 



Four samples of ice cream were secured from different 

 dealers and placed in storage at a temperature varying from 

 0° to 10° F. The bacterial content of these samples aver- 

 aged on the 



Per c.c. 



Initial count 70,000,000 



3rd day 1 20,000,000 



6th day 65,000,000 



gth day 80,000,000 



nth day S°,ooo,oo° 



14th day 13,000,000 



17th day 21,000,000 



20th day 85,000,000 



23rd day ■ 90,000,000 



27th day 225,000,000 



30th day 22,000,000 



34th day 13,000,000 



