658 STATE BOARD OP AGRICULTURE. 



all of several sources. Soil or dust on the pods may have been trans- 

 ferred to the peas in shelling; there may have been dirt on the hands 

 of those shelling the peas which would be transferred to the peas; 

 peas dropped upon the floor, if picked up later would add their quota 

 to the organisms already present; dust from the air may have settled 

 upon the shelled peas in the room or refrigerator when left over night, 

 this incubation period giving an opportunity for any bacteria to mul- 

 tiply to a greater or less extent as favorable moisture and temperature 

 conditions obtained. As the peas shelled and canned the same day 

 showed a much lower percentage of spoilage than peas partly shelled 

 and left until the next day before canning, this last method of con- 

 tamination, at least in so far as an incubation period is furnished, 

 would seem- an important one. 



The percentage of spoilage was much lower in pint cans of peas auto- 

 claved than in the same size cans processed by any other method. This 

 doubtless accounts for the higher percentage of spoilage of home canned 

 peas as they are usually canned by the hot water bath method, in con- 

 trast to the commercially canned product. The results tabulated in 

 Table I suggests strongly that one hour is much too short a processing 

 period in the autoclave for peas canned in the quart size mason jars. 



The commercial canner is especially careful to have his peas canned 

 as soon as possible after cutting. He is also veiy thorough in washing 

 the product before canning. Doubtless, cleanliness is the secret of 

 the low percentage of spoilage as his process consists of heating the 

 cans at 112-115 degrees C. for 35 to 40 minutes, a temperature with- 

 stood by tlie organisms described in this paper. 



The ability to form gas in peas seems to be due to the action of 

 organisms upon some protein or proteins found in peas and not in 

 artificial media. It may be possible to differentiate further between 

 similar organisms by the use of peas or like plant products as a medium 

 since organisms not classified as gas formers were found to produce 

 gas when so tested. 



SUMMARY. 



1. The lowest percentage of spoilage was found in peas processed 

 in the autoclave. 



2. Peas canned immediately after shelling had a comparatively low 

 percentage of spoilage. 



3. Organisms found were all spore forming bacilli. 



4. All organisms withstood from ten to fifteen pounds pressure in 

 Ihe autoclave for ten to twenty minutes. 



5. Nearlj^ all organisms reduced starch to sugar. 



6. Seven of these organisms caused peptonization in milk, 



7. But one organism found failed to produce indol from peptone. 



8. Eight of the organisms found in canned peas produced gas in 

 sterile peas but not in other media. 



9. B. siihtilis, B. ramosus, B. riihcr, B. j)ro(lifjiosus* and B. 

 viscosus produced gas in peas but not in otlier media. This fact 

 suggests additional possibilities in differential identification tests. 



*Ga8 production in eusar broth fermentation tubes has been noted 'with at least one strain of an 

 organism wliich otherwise very closely resembles D. prodigi'osus. (F. L. Rector) 



