Studies Of High Pressure On Physicochemical Characteristics Of Bovine Milk And Denaturation Of Whey Protein

In our project we have studied the effects of high pressure on physicochemical characteristics and whey protein denaturation in bovine milk, under treatment condition of pressure from 0 to 600MPa, combined with different tempratures and duration time of the pressure treatment. At 25℃, and high pressure up to 600MPa for 10 minutes, the casein micelle size changed from 200nm to 110nm. High pressure treatment increased the hydration and dynamic viscosity, but decreased the turbidity of milk, those changing tendency of the physicochemical characteristics were in accord with the changing tendency of the casein micelle size. Under α=0.01 level, pressure, temprature, duration time of the pressure treatment and concentration of sugar had an extreme significant effect of whey protein denaturation. At 25℃, and high pressure up to 600MPa for 15 minutes, 75% of total whey protein were irreversibly denaturated；the higher concentration of sugar displaied the more protective function, and concentration of sugar was decreased,the more smaller denaturation of whey protein was observed.