基于近红外光谱技术,结合不同预处理和特征波长筛选方法,构建小麦专用粉的破损淀粉含量、降落数值、吸水率、稳定时间、拉伸面积、延伸度和最大拉伸阻力的偏最小二乘(Partial Least Squares,PLS)预测模型和总体预测模型,并对模型的预测...基于近红外光谱技术,结合不同预处理和特征波长筛选方法,构建小麦专用粉的破损淀粉含量、降落数值、吸水率、稳定时间、拉伸面积、延伸度和最大拉伸阻力的偏最小二乘(Partial Least Squares,PLS)预测模型和总体预测模型,并对模型的预测能力进行评估。结果表明:去线性趋势(Detrend,DT)是破损淀粉含量和吸水率预测模型的最佳预处理方法,Savitzky-Gloay(SG)卷积平滑是降落数值和拉伸面积预测模型的最佳预处理方法,标准正态变量变换(Standard Normal Variable Transformation,SNV)是延伸度和最大拉伸阻力预测模型的最佳预处理方法。竞争性自适应重加权法(Competitive Adaptive Reweighted Sampling,CARS)可有效提高破损淀粉含量、降落数值、吸水率、拉伸面积和最大拉伸阻力预测模型的预测精度,预测决定系数分别为0.9641、0.7140、0.9755、0.9434和0.8283;连续投影算法(Successive Projections Algorithm,SPA)可有效提高稳定时间和延伸度预测模型的效果,预测决定系数分别为0.7135和0.9530。总体预测模型对稳定时间、拉伸面积和最大拉伸阻力的预测效果均有所提升,剩余预测偏差(Residual Predictive Deviation,RPD)分别从1.86、4.27和2.51提升到2.43、5.26和3.11。综上可知,近红外光谱技术对小麦专用粉品质特性的无损快速检测是有效的、可行的。展开更多
Whole wheat flour is a food raw material rich in macronutrients,but its application in baking industry is limited due to the existence of a large amount of insoluble dietary fiber in bran.In order to make full use of ...Whole wheat flour is a food raw material rich in macronutrients,but its application in baking industry is limited due to the existence of a large amount of insoluble dietary fiber in bran.In order to make full use of this resource,we first screened twelve cellulase-producing strains,and then extracted soluble dietary fiber(SDF)from whole wheat flour after fermentation with 3 strains of Aspergillus sp.and 2 strains of Bacillus sp.,respectively.The effects of different strains on nutritional characteristics,SDF yield,structure improvement,and antioxidant activity of whole wheat flour were compared.The results showed that fermentation of whole wheat significantly increased the yield of SDF,the content of nutritive active substances,and improved the physicochemical structure and antioxidant activity of SDF in vitro.Scanning electron microscopy(SEM),X-ray diffraction and liquidity characteristics show that the fermentation to make whole wheat SDF has more porous microstructure and crystallinity of lower molecular weight.Fourier transform infrared spectrum showed that there were differences in functional group types between soluble dietary fiber in control group(C-SDF)and soluble dietary fiber in the fermentation group(F-SDF).These changes together improved the hydration performance and antioxidant activity of whole wheat SDF,including water holding capacity,oil holding capacity,cholesterol adsorption,1,1-diphenyl-2-picrylhydrazyl(DPPH),2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)and hydroxyl radical scavenging,and lipase activity inhibition.Bacillus sp.SH and Aspergillus oryzae Y21 are ideal strains for fermentation of improved whole wheat,which has the potential of antioxidant properties while improving nutritional properties and food quality.展开更多
基金supported by National Natural Science Foundation of China(32330081).
文摘Whole wheat flour is a food raw material rich in macronutrients,but its application in baking industry is limited due to the existence of a large amount of insoluble dietary fiber in bran.In order to make full use of this resource,we first screened twelve cellulase-producing strains,and then extracted soluble dietary fiber(SDF)from whole wheat flour after fermentation with 3 strains of Aspergillus sp.and 2 strains of Bacillus sp.,respectively.The effects of different strains on nutritional characteristics,SDF yield,structure improvement,and antioxidant activity of whole wheat flour were compared.The results showed that fermentation of whole wheat significantly increased the yield of SDF,the content of nutritive active substances,and improved the physicochemical structure and antioxidant activity of SDF in vitro.Scanning electron microscopy(SEM),X-ray diffraction and liquidity characteristics show that the fermentation to make whole wheat SDF has more porous microstructure and crystallinity of lower molecular weight.Fourier transform infrared spectrum showed that there were differences in functional group types between soluble dietary fiber in control group(C-SDF)and soluble dietary fiber in the fermentation group(F-SDF).These changes together improved the hydration performance and antioxidant activity of whole wheat SDF,including water holding capacity,oil holding capacity,cholesterol adsorption,1,1-diphenyl-2-picrylhydrazyl(DPPH),2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)and hydroxyl radical scavenging,and lipase activity inhibition.Bacillus sp.SH and Aspergillus oryzae Y21 are ideal strains for fermentation of improved whole wheat,which has the potential of antioxidant properties while improving nutritional properties and food quality.
