MEAT BACTERIA 



183 



more especially, in meats and meat products which contain starch 

 and sugar. 



5. Bacteria. — It is not necessary to enter into any extensive 

 discussion of the different species and varieties of bacteria which 

 may occur in and upon meats. The more important bacterial 

 invasions of meats have already been mentioned. The following 

 is a partial Hst of the more important species which the food bac- 

 teriologist may be called upon to look for in meats: 



a. Bacillus botulinus. — Most common in sausages, as already 



Fig. 60. — B. tetani, showing flagellae. 



stated elsewhere. Forms highly virulent toxins and produces 

 rancid changes. 



b. Bacillus tuberculosis. — Will be found in meats of tuber- 

 culous animals. 



c. Bacillus tetani. — May occur in meat products, more es- 

 pecially in gelatin. It is essentially anaerobic but thrives better 

 in association with aerobes, and it produces one of the most 

 virulent toxins known which is, however, very unstable in its 

 chemical composition and easily destroyed. A temperature of 

 60° to 65° C. destroys it and it is also very quickly destroyed on 

 exposure to air and light. The danger from the tetanus bacillus 

 pertains to possible inoculation with the bacillus rather than the 



