以 Alcalase 、Neutrase 及Bromelain 等3 種?同酵素進?水解試驗時， 發現其水解程?順序為: Alcalase >Bromelain >Neutrase ， 其水解?分別為16% 、12% 及9% 。水解曲線皆於3 小時後趨於平緩， 而在其官能性的比較上， 溶解?及乳化能?以Alcalase 的90.3%及39% 最佳， 而Bromelain 則在起泡能?上具有最大的增加幅?135% 。苦味程?則以Alcalase 最苦， Bromelain 與Neutrase 接近。經酵素水解後的黃豆蛋白質水解物， 其營養價值皆有所改善， 而必需胺基酸的組成比?除甲?胺酸(Met) 及?胺酸(Lys) ?低， 其餘皆有所增加。雖然Alcalase 的水解效果較佳， 且對必需胺基酸組成的改?上， 也比其他?種酵素?好， 但在具有?低膽固醇效用之甘胺酸(Gly) 及精胺酸(Arg) 的組成上， 卻明顯比?上Bromelain 及Neutrase ， 其中又以Bromelain 能分別增加0.37%及1.18%最具潛?。 The main objective of this research was to hydrolyze soy proteins with the various commercial proteases. The functional properties and the nutrient value of the hydrolysates were also evaluated. When the commercial proteases were employed for hydrolysis, the degree of hydrolysis with Alcalase after 3 hour was around 16%, which was higher than those with Bromelain 12% and Neutrase 9%. Concerning functional properties, the hydrolysates produced with Alcalase show the best performance in solubility and emulsion capacity of 90.3% and 39%, respectively. In contrast, the products obtained with Bromelain treatment has a great increase (135%) in foaming capacity. In addition, the bitterness level determined directly by tasting was shown as follows: Alcalase>Bromelain>Neutrase. The nutrient value of soy protein hydrolysates obtained with protease treatment was improved. The concentrations of essential amino acids, except for methionine and lysine, all were increased. Although Alcalase has the highest hydrolysis activity and the can improve the compositions of essential amino acid, it reduces the concentration the concentrations of glycine and arginine, which are capable of reducing cholesterol in vivo. Based on the result, the hydrolysis with Bromelain deserves to more attention since it leads to the increase in glycine and arginine contents to 0.37% and 1.18%, respectively.
