was used in every case. Organisms looked for included anaerobes, 

 aerobes, and thermophiles. The anaerobes and thermophiles were 

 not fully identified, there being no positive way of determining their 

 identity. Aerobes were fully identified. 



The standard method followed consisted of obtaining these cul- 

 tures from the fish in each can, i. e., two petri plates were cultured 

 from the meat, one petri plate from the juice, a mass culture from the 

 meat, and an anaerobic glucose agar culture from the meat. The 

 petri plates were incubated at Z7° C. The mass culture was incu- 

 bated at Z7° C. and 55° C. This method would favor the growth of 

 bacteria whose optimum temperature is Z7° and of thermophiles 

 whose optimum temperature is 55° C. The anaerobic culture (glu- 

 cose agar) would favor the growth of anaerobic bacteria whose opti- 

 mum temperatures are Z7° and 55° C. The glucose agar was boiled 

 previously to expel any air which might be in the tube. 



All mass culture bottles, petri dishes, test tubes, spoons, and can 

 openers were thoroughly washed with soap and water, dried, and 

 sterilized. The can was thoroughly washed and dried, and the top 

 held over a gas flame to kill any bacteria remaining. The can was 

 then opened with the sterile can opener, using due care not to con- 

 taminate the contents. After the can was opened the top layers of 

 meat were removed with the sterile spoon; this portion of the meat 

 having been heated, the bacteria would likely be killed. A mass cul- 

 ture was taken from the center meat, consisting of about four grams 

 of meat, which was placed in a small, wide-mouthed bottle containing 

 beef broth. The juice culture was taken with a spoon, which meas- 

 ured about four cubic centimeters, placed in a petri dish and later 

 covered with melted agar. The two meat cultures were placed in a 

 tube, thoroughly ground up with a small sterile pestle, and placed in 

 petri dishes. These cultures were also covered with melted agar. 

 The anaerobic culture was placed in a test tube and mixed with 

 glucose agar. All these cultures were then incubated at 2)7° C. for 

 from three to five days. The mass and anaerobic cultures were later 

 removed and incubated at 55° to detect thermophiles. 



The media for identification were potato, lactose fermentation 

 tube, glucose fermentation tube, plain milk, litmus milk, and gelatine. 



Incubation. The cans examined were all incubated at room tem- 

 perature from 5 to 26 days. In no case was any swell or leaky can 

 noticed. With the first lots of cans the shortest process was exam- 

 ined first, while with the second lot the longest process was examined 

 first. The cans, as stated above, were heated or exhausted at 212° F, 



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