高温-复合酶法改性小米糠膳食纤维工艺优化及结构与功能分析  

Optimizing the Preparation Process of Dietary Fiber from Millet Bran Modified by High Temperature-Composite Enzyme and Analysis of Its Structure and Functional Properties

作　　者：丁彩云 糟帆 马玉婷 刘军[1] 刘敦华[1] 傅婧 Ding Caiyun;Zao Fan;Ma Yuting;Liu Jun;Liu Dunhua;Fu Jing(School of Food and Wine,Ningxia University,Yinchuan 750021)

机构地区：[1]宁夏大学食品与葡萄酒学院,银川750021

出　　处：《中国粮油学报》2022年第12期67-75,共9页Journal of the Chinese Cereals and Oils Association

基　　金：宁夏回族自治区重点研发计划(2020BFH03003)。

摘　　要：采用高温-复合酶法改性脱脂小米糠膳食纤维(DF)并优化工艺;通过扫描电镜(SEM)、X-射线衍射(XRD)、傅里叶红外图谱(FT-IR)及吸附性能等分析改性膳食纤维的结构及功能性质。结果表明,高温-复合酶法改性小米糠膳食纤维的最佳工艺条件为:复合酶比例(木聚糖酶∶纤维素酶)为2∶1、复合酶质量分数2%、酶解温度50℃、酶解时间1.50 h,在此条件下改性后小米糠可溶性膳食纤维(SDF)得率达到(17.27±1.57)%;SEM表明改性后样品形态均发生改变,呈现多孔隙网络结构,毛细管吸附作用增强,XRD表明DF改性后纤维晶型保持不变,仍为纤维素Ⅰ型,结晶度增大,FT-IR显示改性后吸收峰的峰型、位置均未有明显改变;改性后葡萄糖、胆固醇的吸收能力分别增加23.05%和0.813%(pH 2)、3.195%(pH 7)且具有显著性差异,同时α-淀粉酶的抑制率增加了13.47%。In the present paper, high temperature-composite enzyme method was used to modify defatted millet bran dietary fiber(DF) and optimize the process;the structure and functional properties of the modified dietary fiber were analyzed by scanning electron microscopy(SEM), X-ray diffraction(XRD), Fourier infrared spectroscopy(FT-IR) and adsorption properties. The results revealed that the optimum conditions for the modification of dietary fiber from millet bran by high temperature-composite enzyme method were: the ratio of composite enzyme(xylanase∶cellulase) of 2∶1, the mass fraction of composite enzyme of 2%, the enzymatic digestion temperature of 50 ℃, and the enzymatic digestion time of 1.50 h. Under these conditions, the yield of soluble dietary fiber(SDF) from millet bran was(17.27±1.57)% after modification. XRD indicated that the crystalline shape of the fibers remained unchanged after DF modification, still cellulose type I, and the crystallinity increased, FT-IR indicated that the peak shape and position of the absorption peaks did not change significantly after modification;the absorption capacity of glucose and cholesterol increased by 23.05%, 0.813%(pH 2) and 3.195%(pH 7), respectively, after modification with significant differences, while the inhibition rate of α-amylase increased by 13.47%.

关 键 词：脱脂小米糠 膳食纤维改性 工艺优化 结构表征 功能特性 

分 类 号：TS209[轻工技术与工程—食品科学]