“…According to Fox (1981A,B), when milk is heated at elevated temperatures for prolonged periods of time, additional acidity develops as a result of (1) the production of organic acids, principally formic, from lactic acid, (2) the release of hydrogen ions by precipitation of primary and secondary calcium phosphate, and (3) the release of hydrogen ions by hydrolysis of casein phosphate and its subsequent precipitation as Ca3(P04b. These reactions contribute 50,20 and 30%, respectively, to pH decline (Pyne and McHenry 1955).…”