Sterilizing the Canned Product 435 



through a given weight of one vegetable as it does through 

 that of another. With a temperature of 236° Fahr., the 

 center of a two-pound can of peas has been known to 

 attain the maximum in ten minutes, whereas, in the 

 case of corn, this temperature was not attained at the 

 center until after the can had been exposed to 250° Fahr. 

 for forty minutes. Hence, the sterilization of canned 

 corn requires higher temperatures and. longer exposure 

 than are required for the sterilization of canned peas. 



"The bacteria capable of destroying canned goods are 

 not only of different species, but, what is of more im- 

 portance to the canners, the spores of different species 

 are capable of withstanding different amounts of heat- 

 ing. As a result of this, canners who have been processing 

 successfully at a low temperature for a number of sea- 

 sons suddenly find themselves in trouble when a more 

 resistant species gets into the cans." In an outbreak of 

 swelling, two-pound cans of peas were processed at 

 230° Fahr. for thirty minutes, and the swelling of the 

 cans was noticed in the stock-room in twenty days. The 

 peas in most of the swelled cans emitted a disagreeable 

 odor, " the bodies of the peas were mushy and the skins 

 inflated with gas, like miniature balloons. The liquor 

 was darkened and of a greenish tinge, due to the small 

 particles of the ruptured peas." Large numbers of bac- 

 teria were present in the spoiled cans, while similar 

 unspoiled cans proved to be sterile. 



The organism that caused this trouble was an anaero- 

 bic, rod-shaped, spore-forming bacillus, that produced 

 the characteristic swelling when inoculated into cans of 

 sterile peas. Such cans, when kept at blood-heat. 



