DIRECT EXAMINATION 



53 



In a general way, the number of micro-organisms in food prod- 

 ucts and in liquids intended for internal use, not including the fer- 

 mented products, is negligible when they do not exceed 250,000 

 per cc. (ranging from 5000 per cc. to the maximum). In 'fer- 



FIG. 13. Various stages in the germination of spores in catsups. Note trans- 

 verse septation and branching of the hyphse. Germinating spores may be traceable 

 to the tomato from the field or they may be from spoiling factory pulp. (Bitting, 

 Bull. 119, Bureau of Chemistry, U. S. Dept. oi Agriculture.) 



mented products, as cider, vinegar, wines, beer, etc., the number 

 of organisms present may be much greater, but even here the 

 quantitative estimates generally become negligible if the modern 

 methods of purifying or clarifying (through sedimentation, the 

 use of albumen, gelatin, casein, etc.), nitration, centrifugalization, 

 and sterilization are carried out. Of course, in such products as 



