592 BACTERIA IN ARTICLES OF FOOD. 



culture experiments. He describes five species, designated Bacillus 

 A, B, C, D, and E, which are commonly present, and to which the 

 acid fermentation of the dough is ascribed. 



In Graham bread which had undergone changes making it unfit 

 to eat, Kratschmer and Niemilowicz have found the Bacillus mesen- 

 tericus vulgatus, which appears to have been the cause of the fer- 

 mentation, which was produced in bread having a slightly alkaline 

 reaction by inoculating it with a pure culture of this bacillus. The 

 infected bread has a brownish color, a peculiar odor, and becomes 

 sticky and viscid. 



Uffelmann (1890) has also studied the bacteria in spoiled rye bread, 

 and obtained, in addition to common mould fungi, Bacillus mesente- 

 ricus vulgaris and Bacillus liodermus. 



Bernheim (1888) has examined various grains used as food, with 

 reference to the presence of bacteria, and claims to have demon- 

 strated their presence by staining thin sections, and also by cultures, 

 in corn, wheat, rye, barley, and peas. He supposes that they find 

 their way from the earth through the roots and stems of plants. 

 This appears to be very doubtful, in view of the researches of other 

 observers, and further researches are necessary before we can accept 

 the fact as demonstrated that they are usually present in healthy 

 kernels of the grains mentioned. 



