不同来源膳食纤维的结构和理化性质分析

The structure and physicochemical properties of different types of dietary fiber

以鹰嘴豆膳食纤维(dietary fiber,DF)、葡萄DF、大豆DF和麦麸DF为试验原料,研究了4种不同来源DF的理化特性(持水力、持油力、膨胀力、粒径、溶解度、热特性)之间的差异,并用傅里叶变换红外光谱、扫描电镜表征其结构变化。结果表明:鹰嘴豆DF的持水力、持油力最高,分别为2.45,1.97g/g;麦麸DF的膨胀力最好,为3.18mL/g;4种膳食纤维的溶解度与温度呈正比,其中鹰嘴豆DF的溶解度最高;傅里叶变换红外光谱分析发现,4种DF的红外吸收光谱基本相同,均含有C—H、O—H、C=O、C—O—C键;热特性分析结果表明豆类DF有更高的变性温度,而麦麸DF的热稳定性最好。扫描电镜结果显示鹰嘴豆DF颗粒表面带有无规则褶皱,褶皱存在使DF表面积增大,从而表现出更高的持水力和持油力。综上,鹰嘴豆DF可以作为良好的保水保油剂,应用于肉制品、乳制品等食品加工,提升产品品质。

The physicochemical characteristics,including water holding capacity,oil holding capacity,swelling capacity,particle size,solubility,and thermal properties,of chickpea dietary fiber(DF),grape DF,soybean DF and wheat bran DF were evaluated in this study.The structural properties of DFs were characterized by Fourier transform infrared spectrum and scanning electron microscope.The results showed that chickpea DF had the best water holding capacity and oil holding capacity,at 2.45 g/g and 1.97 g/g,respectively.Wheat bran DF had the best swelling capacity(3.18 mL/g).The solubility of four dietary fibers were positively proportional to temperature,among which the solubility of chickpea DF was the highest.Fourier transform infrared spectral analysis indicated the infrared absorption spectrum of four DFs were basically the same.And they all had C—H,O—H,C=O,C—O—C.Thermal characteristics analysis showed that the modified temperature of beans DFs were higher than others and the thermal stability of wheat bran DF was best.Scanning electron microscopic analysis confirmed chickpea DF had irregular folds on the surface.DF with folds showed higher water holding capacity and oil holding capacity.In order to improve product quality,chickpea DF can be applied in meat products,dairy products and other food processing,as a good water and oil retention agent.