유청 단백질 가수분해물의 유화특성

This experiment was carried out to study changes in solubility and emulsifying properties of whey protein. Whey protein hydrolysates were obtained from tryptic hydrolysis of whey protein concentrate at pH 8.0 and 37℃ for 6 hours. Emulsifying activity of whey protein concentrate with trypsin, α-lactalbumin was not easily broken down. But β-lactalbumin was hydrolysed rapidly from the early stage of hydrolysis, producing several low molecular weigh peptides, which have to participate in increasing emusifying activity. The solulbility of hydrolysates tended to increase depending on hydrolysis time; however, there was a gradual decrease after 5 hours. The hydrolysate had a minimum solubility near the isoelctric point range (pH 4~5). The more hydrolysed the whey protein concentrates, the more soluble they are near the pI. They are more soluble above pH 6. Emulsifying activity of hydrolysates showed similar results to solubility. Creaming stability gradually increased when hydrolysis increased, increasing rapidly above pH 8 after 4 hours of hydrolysis.