Bacteria in the Cheese Industry. 177 



able to their growth, only small "pin holes" may appear; 

 if, on the contrary, the fermentative process takes a more 

 violent course, such as would be the case in a "floating" 

 milk, then the test curd will be spongy and full of holes 

 as in fig. 38. Sometimes the curds will show no evidence 

 of gas, but their abnormal condition can be recognized 

 from the "mushy" texture and the presence of "off" 

 flavors that are materially intensified by keeping them 

 in closed bottles. The odor should always be noted with 

 care, as this is of more importance than the gas which 

 can be eliminated to a large extent by proper manipula- 

 tion during the manufacture of the cheese. 



FIG. 38. Curd from a badly tainted milk. Large ragged holes mechanical 

 small " pin holes " due to gas. 



186. Bitter cheese. Bitter flavors are sometimes 

 developed in cheese especially where the ripening process 

 has not been fully completed, or where improper temper- 

 atures have been maintained for a considerable length of 

 time. Several organisms associated with this abnormal 

 fermentation have been noted. 



Guillebeau 1 isolated several forms from Emmenthaler 



l Guillebeau, Landw. Jahr.. 1890, p. 27. 

 12 B. 



