酶-碱结合法提纯豆渣纤维及其特性表征

摘要

以豆渣为原料,探讨了酶-碱结合法提纯豆渣纤维的工艺条件.结果表明,碱处理和蛋白酶处理的最佳工艺条件分别为:碱处理时间60min、温度65℃、pH11,蛋白酶的添加量0.3%(w/w)、酶解时间1h、酶解温度55℃、pH6,此时产品的得率为80.47%.对处理后豆渣的红外光谱和扫描电镜分析表明,酶-碱结合法可以有效去除附着在纤维表面的蛋白质、脂类等物质,使纤维表面变得光滑.碱处理后豆渣纤维的平均长度、宽度减少,蛋白酶处理后纤维长度和宽度基本没有变化,酶-碱结合处理后纤维的平均聚合度和分子量都有一定下降.%The soybean dreg fibers were prepared by the methods of alkaline solution extracting and enzymatic hydrolysis from byproduct of soymilk .The treatment conditions of alkali treatment and protease hydrolysis were discussed by orthogonal test .The results showed that the optimum tech-nology condition of alkali treatment was that pH value was 11 ,soaking time was 60 min and soaking temperature was 65 ℃ .The condition of protease hydrolysis was that the ratio of enzyme to sub-strate was 0 .3% ,pH value was 6 ,hydrolysis time was 1 h ,the temperature was 55 ℃ .Under the a-bove conditions ,the yield of product was 80 .47% .The FTIR spectrum and SEM were indicated that the protein and lipid attached to the fiber surface ,they could be effectively removed by alkaline solu-tion extracting and protease hydrolysis and they made the fiber surface smooth .After alkali treat-ment the average length and width of soybean fiber decreased .However ,the fiber length and width could not be changed obviously after protease hydrolysis .The average polymerization degree and molecular weight of soybean fibers decreased after alkali and protease hydrolysis .