BOTULISM AND HOME CANNING 11 



Table 2. — Food Involved in Outbreaks of Botulism From 

 Home- Canned Foods. 



Food Number of Food Number of 



Outbreaks Outbreaks 



String beans 57 Celery 



Corn 30 Chili and beans 



Spinach 12 Chili peppers 



Beets 10 Corn and Chili peppers 



Asparagus 9 Eggplant and vegetable mixture. . . . 



Beet and other greens 8 Figs 



Pears 7 Okra (and beans) 



Peppers 4 Pickled tongue 



Apricots 3 Pork 



Chile con carne 3 Potatoes 



Tuna 3 Pumpkin 



Mushrooms .■ 2 Smoked salmon 



Salmon 2 Soy beans 



Tomatoes 2 Soup mixture 



Black-eyed beans 1 Vegetable salad 



Carrots 1 Miscellaneous 4 



Carrots and peas 1 



Cauliflower 1 Total 175 



Although botulism is generalh* associated with low-acid foods, apricots, pears, 

 figs, and tomatoes have been implicated in outbreaks. According to more recent 

 information, the mold growth which may occur when these products are under- 

 sterilized is capable of forming a favorable environment for the development and 

 growth of CI. botulinum and other organisms. As it grows, the mold may reduce 

 the acidity in the jar, or in a portion of the jar, to the point where bacterial 

 growth can take place. 



Many of the case histories of botulism outbreaks show that the foods were 

 canned by methods which are recognized as being inadequate. The so-called 

 "open kettle" method of canning has been responsible for many outbreaks. The 

 boiling water bath method of processing has probably been implicated more 

 than any other. The outbreaks from foods canned in a pressure canner provide 

 evidence that this piece of equipment may give a false sense of security unless it 

 is operated correctly. And, as has been discussed previously, the failure of people 

 to properly boil low-acid home-canned foods prior to tasting them might be given 

 as a reason for most of the botulism outbreaks. Even if a food contained this 

 toxin, it would be destroyed by boiling and in many cases an off odor would be 

 given off which would indicate to the housewife that the food was unfit for con- 

 sumption. 



WHERE IS CLOSTRIDIUM BOTULINUM FOUND? 



At least five different types or strains of CI. botulinum are recognized at the 

 present time: 



Type A: A common soil anaerobe of the Western States, less frequently en- 

 countered in the Atlantic States, the Great Plains, the Mississippi 

 Valley. Frequently associated with virgin mountain or forest soil 

 but may be present in cultivated garden and field soils. Involved in 

 many botulism outbreaks, particularly in the West. Produces a 

 toxin of high potency. 



