SYNERGIC EFFECT OF UREA AND ALDEHYDES ON THE HEAT-STABILITY OF CONCENTRATED SKIM-MILK

When urea is added to concentrated skim-milk (22-5 total solids) no increase in heat stability is observed. However, a similar addition of urea to concentrate stabilized with aldehyde brought about a significant further increase in heat stability. Urea can further stabilize concentrated skim-milk only when aldehyde addition has brought about a change in coagulation mechanism from the normal 2-stage process to a single-stage coagulation. These results can be related to the 2 coagulation mechanisms observed in unconcentrated milks. © 1979, Proprietors of Journal of Dairy Research. All rights reserved.