MICROBIAL FOOD POISONING 591 



unless B. bolulinus is excluded by critical selection of sound materials 

 and cleanliness throughout the canning process. 



Signs of spoilage due to B. botulinus may not be evident at all. 

 Careful examination will often reveal gas bubbles in the container, an 

 odor suggesting rancid cheese and a mushy disintegrated appearance 

 of the solid contents. Canned foods showing any of these signs should 

 never be tasted until they have been cooked again. Indeed, Dickson 

 concludes that all home canned foods should be cooked again before 

 being eaten. Boiling for five minutes just before serving the food 

 practically removes the danger of botulism. 



Ergotism is a disease characterized by cachexia, gangrene and con- 

 vulsions. It is caused by eating the fungus, Claviceps purpurea, which 

 grows as a parasite upon rye. The grain of this parasite has a consid- 

 erable commercial (medicinal) value sufficient to pay for its separation 

 from rye where it occurs, so there is little economic excuse for food 

 poisoning from this cause. 



Beriberi or kakke is an acute or chronic nervous disorder which has 

 been observed especially in the Orient, Japan and the Philippine Is- 

 lands, although it has also been found in Brazil, in Labrador and rather 

 frequently among sailors after long sea voyages. At one time the 

 disease was ascribed to the use of fish as food, later to the use of rice. 

 Modern studies, especially those of Chamberlain, Vedder and theii 

 associates in the Philippine Islands, have shown that beriberi may 

 be prevented by including beans, unpolished rice or rice hulls in suffi- 

 cient quantity in the diet and furthermore that those already afflicted 

 with the disease usually recover completely when given these foods 

 or when treated with an alcoholic extract of rice polishings. The 

 curative principle of rice polishings has been studied by Funk who 

 has named it vitamine. He ascribes the causation of beriberi to a lack 

 of this supposedly necessary vitamine in the food and this theory has 

 been very favorably received. It must be acknowledged, however, 

 that the etiology of beriberi is still not convincingly proven. The 

 discovery of a remedy which eradicates a given disease is not sufficient 

 to prove that the lack of this particular therapeutic agent is the es- 

 sential cause of the disease. 



Pellagra is a cachexia, characterized by a definite sort of skin erup- 

 tion, which has been ascribed to the use of maize (Indian corn) as 

 food. This disease is discussed in a separate section (page 865). 



