188 Dairy Bacteriology. 



too far, for the removal of the sugar permits taint-produc- 

 ing organisms to thrive. 1 



The temperature at which the cheese is cured also mate- 

 rially affects the development of gas. At high curing tem- 

 peratures, gas-producing organisms develop rapidly; there- 

 fore more trouble is experienced in summer than at other 

 seasons. 



If milks which are prone to undergo " gassy " develop- 

 ment are excluded from the general supply, it would be 

 possible to eliminate the source of the entire trouble. To 

 aid in the early recognition of such milks that are not ap- 

 parently affected when brought to the factory, fermenta- 

 tion or curd tests (p. 76) are of great value. The use of 

 this test in the hands of the factory operator often enables 

 him to detect the exact source of the trouble, which may 

 frequently be confined to the milk delivered by a single 

 patron. 



"Fruity" or "sweet" flavor. Not infrequently the 

 product of a factory may acquire during the process of 

 ripening what is known as a " sweet" or u fruity" flavor. 

 This flavor resembles the odor of fermented fruit or the 

 bouquet of certain kinds of wine. It has been noted in 

 widely different sections of the country and its presence 

 bears no relation to the other qualities of the cheese. The 

 cause of this trouble has recently been traced 2 to the pres- 

 ence of various kinds of yeasts. Ordinarily yeasts are 

 rarely present in good cheese, but in cheese affected with 

 this trouble they abound. The addition of starters made 

 from yeast cultures resulted in the production of the unde- 

 sirable condition. 



1 Babcock and Russell, 18 Kept. Wis. Expt. Stat., 1901. 



3 Harding, Rogers and Smith, Bull. 183, N. Y. (Geneva) Expt. Stat., Dec., 1900. 



