摘要 : The effect of heating (72 degreesC/15 s and 92 degreesC/60 s) of milk reconstituted from low-heat nonfat dry milk (NDM) and medium-heat NDM on the molecular state of proteins was studied. Heating at 92 degreesC was found to affect... 展开 The effect of heating (72 degreesC/15 s and 92 degreesC/60 s) of milk reconstituted from low-heat nonfat dry milk (NDM) and medium-heat NDM on the molecular state of proteins was studied. Heating at 92 degreesC was found to affect the protein integrity in low-heat NDM and medium-heat NDM in a different way. Lower stability of micellar casein (a decrease in the content by 4.8%) and smaller beta-lactoglobulin (beta-lg) content of the micellar pellet for medium-heat NDM (44%) than low-heat NDM (68%) were found. The effect of heating reconstituted milk on content and composition of protein particles insoluble at 110,000 g was dependent to a higher degree on the micellar kappa-casein and soluble Ca contents than on the degree of whey protein denaturation. This was indicated by the change in the Ca/P (w/w) ratio in non-micellar fractions that decreased from 0.96 to 0.93 for heated medium-heat NDM and increased from 0.93 to 0.99 for low-heat NDM. 收起