酶法制备豆皮低聚木糖的工艺研究

Use of Xylanase for Enzymatic Preparation of Xylooligosaccharides from Soybean Hull

利用木聚糖酶酶解豆皮制备低聚木糖,通过单因素试验考察酶解温度、pH值、时间、料液比以及酶添加量对酶解液中低聚木糖含量的影响,并在此基础上通过正交试验确立最佳酶解工艺条件:酶添加量0.3%、pH4.3、料液比1:15(g/mL)、温度40℃、酶解时间2h。该最佳工艺条件下,总还原还原糖含量为5.74mg/mL。通过离子色谱检测酶解液中的糖分组成,发现酶解液中的单糖以木糖为主,相对含量达到54.99%。

In this study,soybean hull was first subjected to sequential pretreatment with an aqueous sodium hydroxide solution followed by an aqueous ammonium oxalate solution for the removal of protein and pectin and then hydrolyzed with xylanase to prepare xylooligosacccharides.To maximize total sugar content in soybean hull hydrolysate,this study emphatically focused on optimizing hydrolysis process of soybean hull.Effects of hydrolysis parameters including hydrolysis temperature and time,pH,ratio of solid to liquid and xylanase amount on total sugar content in soybean hull hydrolysate were analyzed by single factor and orthogonal array design methods.Results indicated that the optimal values of these parameters were as follows：hydrolysis for 2 h at 40 ℃,pH 5.3,a ratio of solid to liquid of 1：15 and an enzyme amount of 0.3%.The total sugar content in soybean hull hydrolysate obtained under such conditions was 5.74 mg/mL.Ion chromatographic detection revealed that the predominant monosaccharide in soybean hull hydrolysate was xylose with a relative content of 54.99%.