Heat Coagulation of Milk

Abstract

A method of determining coagulation times at various temps. is described, and results obtained over the temp. range of 110[degree] to 160[degree]C. are reported for both cow''s and goat''s milk. Considerable variation was found in the coagulation time of various samples at a given temp. Thus, at 115[degree] the milk from one cow coagulated in 151 min., whereas that from another cow required 480 min. With a set of samples, however, the coagulation time at one temp. was not necessarily an index to the order of coagulation at a different temp. The relative stabilities of samples at one temp. do not indicate what their relative stabili-ties will be at another. There seemed to be a characteristic difference between cow''s and goat''s milk, since coagulation times for goat''s milk at 135[degree] are about the same as for cow''s milk at 155[degree] to 160[degree]. Although, over a limited temp. range, most samples show a fairly straight-line relationship between coagulation temp. and logarithm of coagulation time, a significant deviation from this relationship was found to exist when the temp. range of 110[degree] to 160[degree] was considered.