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PASTEURISATION OF MILK AND CREAM. 



In this Journal for June 1900 a review was given of the 

 results of certain experimental investigations relating to the 

 pasteurisation of milk and cream carried out by Messrs. 

 Farrington and Russell at the Wisconsin Experimental 

 'Station, Wisconsin. These experiments were designed to 

 ascertain the effect of a temperature of 140 deg. Fahr. on the 

 consistency and creaming property of milk, and whether 

 exposure to that temperature would destroy the bacillus of 

 tuberculosis. It had been usually held that to destroy this 

 bacillus exposure to a temperature of 155 deg. Fahr. for 

 15-20 minutes was requisite ; but milk or cream pasteurised 

 at 155 deg. Fahr. becomes much thinner in consistency, 

 although the amount of fat remains altered. Moreover, the 

 cream in such milk does not rise to the surface, and the 

 impression might be created that the article is deficient in 

 butter fat owing to the fact, discovered by Messrs. Babcock 

 and Russell in 1896, that in milk heated to more than 140 deg. 

 Fahr. the fat globules become uniformly diffused throughout the 

 product instead of being aggregated in tiny clots or clusters 

 as is the case in normal milk. Certain investigations by 

 Dr. Theobald Smith as to the exact temperature at which the 

 vitality of the tubercle bacillus was destroyed had, however, 

 shown that an exposure of 140 deg. Fahr. for twenty minutes 

 was usually sufficient to destroy the organism of bovine 

 tuberculosis. The confirmation of this result by tests on a 

 practical scale would permit of such modification of the 

 pasteurising temperature as would do away with the usual 

 objection to pasteurised products, and Messrs, Farrington 

 and Russell's experiments were accordingly directed to the 



