STUDIES IN THE HEAT RESISTANT ORGANISMS OF COLD 



RACKED CANNED REAS. 



Technical Bulletin No. 47 



INTRODUCTION. 



During the past few years much has been said about food conser- 

 vation, the home garden and home canning. Especially has the demon- 

 strator attempted to help the housewife save garden vegetables which 

 would otherwise be wasted. 



These efforts Lave been largely successful. In many instances, how- 

 ever, canned vegetables have spoiled. The reason for spoilage has been 

 given as due to the use of vegetables not fresh, or failure to follow the 

 directions as given in the most recent Government bulletins on home 

 canning. The question thus arose as to whether the spoilage was due 

 to either of these causes or to both, or if this trouble might have some 

 other origin. 



It has been tlie writer's intention during the course of this investi- 

 gation to solve this problem if possible and determine the cause for the 

 very much larger proportion of spoilage among home canned foods as 

 compared with those canned commercially. 



REVIEW OF LITERATURE. 



Rrobably the first bacteriological examination of spoiled canned goods 

 was reported by Russell (2G) in 1S95 in connection wdth the occurrence 

 of "swells" in canneries of Wisconsin. In the paper "Gaseous Fermenta- 

 tions in the Canning Industry" he cites the isolation from swelled canned 

 peas of two bacilli which he did not identify. He recommended the 

 increase of temperature to 242 degrees F. and the pressure to fifteen 

 pounds for twenty-eight minutes. 



In 1904, Harding and Nicholson (20) examined an outbreak of spoil- 

 age in canned peas. Tliey found spoilage in Avhich there was simjdy 

 souring of the product and also spoilage in which there was gas present 

 and malodor. A small rod or coccus caused the former and a plump 

 rod with terminal spores which grevv- vigorously in the presence of 

 sugars at 37 degrees C. caused the latter. Limits for successful pro- 

 cessing were determined. 



Duck wall (17) devoted one chapter in his book on "Canning and 

 Rreserving"' (1905) to canned i^eas in which he discussed the history 

 of peas, their parasites, their composition and food value, methods of 

 canning, and bacteria associated with spoilage. The organisms dis- 

 cussed were those found by himself and others. He mentions lactic 

 acid bacteria, B. butijricus, B. mescntcriciis viiUjdttis, "A butyric acid 

 bacillus which was a strict anaerobe with terminal spores similar to 

 B. tctani," B. megatherium, B. prodigiostis, B. subtilis, B. rnesentericus 

 ruher, B. mijcoides and some organisms not named but described. He 



