In dairy practice a starter or culture of a lactic acid ba,cillus is used 

 to overcome the g-assy fermentation of milk, and in order to quantitatively 

 establish the working- of this process, a number of experiments were in- 

 stituted, in which gas-producing and lactic acid organisms were mixed 

 together in order to study their antagonistic relations. The results of 

 these experiments in general showed that the number of gas-producing 

 germs decreased with the increase of lactic acid bacteria. Occasionally, 

 however, some organisms were experimented with which were not so ad- 

 versely influenced by the lactic acid germs. 



■ ■ * ^ *» • • • 



Gas-producing bacteria ; luagiiified 1500 

 diameters. 



Cheese Experiments. A number of cheese were made from milk to 

 which various quantities of a culture of gas-producing bacteria was 

 added. A few of these experiments my be cited : — A cheese was made on 

 the 5th of October from 300 pounds of milk to which 2 pounds of a 24 

 hour old milk culture of a gas-producing variety was added. This cul- 

 ture was acid, very gassy, with a bitter, astringent taste. The cheese 

 curfl was also very gassy, floating on the top of the whey. After making, 

 the cheese was put into the curing-room with an average temperature of 

 55 degrees F., and bacteriological analyses were made from time to time. 

 At the age of 21 days, the percentage of gas-producers was 76, at the end 

 of 38 days, 71 ; and at the end of 52 days, 11 ; and at this stage, the 

 cheese showed white and grey lines and spots, an appearance known 

 amongst cheesemakers as "mottled." The cheese was scored, but no 

 points could be given to it for flavor. The odor was something like rot- 

 ten meat, and the mottled appearance was very striking. 



[5] 



