
BACTERIA IN THE DAIRY. 89 
Species Vo, 52. 
When ripened at ordinary temperatures and for ordinary 
length of time the cream remains thin although it becomes filled 
with bubbles of gas indicating the probable formation of carbon 
dioxide. If the temperature is raised the gas is more abundant 
and the cream becomes thicker. The reaction is acid when the 
ripening takes place in a typical fashion. The odor is that of 
typical sour milk or sour cream and the taste the same. The 
butter made therefrom is good with a slight acid flavor. The 
aroma is not developed but the butter has the acid flavor which 
is desired as one of the factors of a high quality butter. This 
organism is, therefore, one of the better species of cream bacteria 
and undoubtedly aids in producing a proper cream ripening and 
butter flavor. 
Species No. 53. 
This organism makes the cream more or less thick according 
to the length of the ripening, and produces an abundant gas. 
When the cream that has been ripened with No. 53 is agitated 
the gas rises in a mass of bubbles to the surface and sometimes 
collects ina froth. ‘The cream is curdled if the ripening con- 
tinues long enough. It is decidedly acid and has the well-known 
typical odor of sour milk. The taste is also like that of sour 
milk. Butter made therefrom possesses a moderate acid flavor 
which may be decidedly too acid if the ripening continues too 
long. There is not produced, however, any proper butter aroma, 
and although the butter is tolerably good it is not first-class 
butter from lacking the especially desirable character of high 
quality product. 
Species No. 54. 
No. 54 has very little effect upon the appearance of the cream 
unless the ripening is continued for a long time. ‘The cream 
remains thin, no gas is produced, but it is rendered decidedly 
acid and acquires a peculiar, penetrating, rather strong odor, 
somewhat resembling garlic. The butter made therefrom is 
never of very good quality, although in some cases when the 
ripening has not been carried too far the butter is tolerably good. 
It is, however, never possessed of a proper butter aroma and 
usually has an unpleasant taste. The species is an unfavorable 
one for butter-making. 
