OPENNESS IN CHEESE.

Manawatu Standard, Volume LVIII, Issue 176, 25 June 1938, Page 18

OPENNESS IN CHEESE.

SOLVING THE PROBLEM. QUALITY MILK ESSENTIAL. “Problems affecting tile composition and flavour of freshly drawn milk, the quality, yield and storage of cheese, the keeping quality of butter, and the prevention of contamination of dairy products with moulds, have been extensively studied by the Dairy Research Institute during the past year,” said Professor W. Riddet in the course of an address to the annual conference of the National Dairy Association at New Plymouth. The professor dealt with several of these aspects, his remarks on the maintenance of milk quality being of particular interest to the dairy farmer who supplies a cheese factory. “Careful control of the milk supply is essential in any effort to make cheese closer in texture,” Professor Riddet said. “There are two apparent modes of approach to this prob-lem-improvement of the raw milk supply on the farm and special treatment of the milk at the factory. There is a definite limit to the latter, because excessive heat treatmeht of milk is known to interfere with the character and quality of the cheese. While, therefore, further work on this is proceedings, it is necessary in practice to concentrate on the application of general principles concerning the improvement of the raw milk supply. Obviously ,the greater the number or the greater the activity of the harmful bacteria introduced to the milk, the greater will be their effects.” The original source of the organisms had not been clearly defined and it was exceedingly difficult to reach a conclusion, said the speaker. There was reason to however, that great numbers of them were to be found "on pasture, and they abounded in silage. They readily, therefore, passed to the cow’s coat and during milking gained access to the milk. Once they were present in the milk supply they multiplied, especially if the milk was not immediately cooled, and they also infected all parts of the milk plant and cans. If these were not thoroughly washed and sterilised after each milking an accumulation started to gather, with the consequence that, as time went on, the daily milk supply became more heavily contaminated. The combination of unclean milking and lack of cooling brought about a very serious condition. When the milk was delivered to the factory it was generally pasteurised, but while pasteurisation destroyed a considerable percentage of the contaminating bacteria _it could not destroy all of them, and it so happened that some of the worst types of organisms were somewhat resistant to the pasteurising temperatures normally used in cheese r making. ‘‘Reviewing the whole question of the control of open texture in cheese,” Professor Riddet said, “it will be realised that the solution of the problem lies in the careful control of the milk supply, in the use of selected and active starters, careful manufacture of the cheese, and_ careful storage. Much work yet remains to be done before the complete control of openness can be brought about, but it is confidently believed that sufficient progress has been made to provide some, assistance.”