大豆种皮多糖对蛋白乳液凝胶特性及微观结构的影响

乳液凝胶可用于替代部分脂肪,降低蛋黄酱等食品中饱和脂肪酸的含量,并作为递送生物活性物质的载体。采用热处理的大豆分离蛋白(soy protein isolate,SPI)和大豆种皮多糖(soybean hull polysaccharide,SHP)制备乳液凝胶,利用流变仪、傅里叶变换红外光谱仪、X射线衍射仪、扫描电镜和质构仪分析不同SHP质量分数(0、0.15%、0.30%、0.45%、0.60%)对乳液凝胶结构、流变特性、凝胶性和乳化稳定性的影响。结果表明:随着SHP质量分数的增加,乳液凝胶的微观结构更加致密,储存稳定性、G′和G″值、相对回收率逐渐增加。随着SHP质量分数的增加,乳液凝胶的表观黏度增加,并在SHP质量分数为0.45%时,达到最大。红外光谱和扫描电子显微镜观察结果显示,SHP和SPI之间存在分子间相互作用和氢键作用。储藏实验结果证实,储存7d后乳液凝胶的储藏稳定性随着SHP添加量的增加而增强,当SHP质量分数为0.45%时,乳液凝胶稳定性较高。研究旨在为SHP在食品乳液凝胶中的开发和应用提供理论依据。

Effect of Soybean Hull Polysaccharide on Properties and Microstructure of Protein Emulsion Gel

Emulsion gels can be used to replace part of the fat, reducing the amount of saturated fatty acids in foods such as mayonnaise, as delivery vehicle for active bioactive substances. The emulsion gels were prepared by heat-treated soy protein isolate (SPI) and soybean hull polysaccharide (SHP). The effects of different SHP contents (0,0.15%, 0.30%, 0.45%, 0.60%) on the structure, rheological properties, gelation properties and emulsion stability of the emulsion gels were investigated using rheometer, Fourier transform infrared spectrometer, X-ray diffraction, scanning electron microscopy and texture analyzer. The results showed that the microstructure of the emulsion gel become denser and the storage stability, G′ value, G″ value and the relative recovery of the emulsion gels increased as the additive amount of SHP increased. The apparent viscosity of the emulsion gels also increased with the increase of SHP addition and reached maximum at 0.45% SHP. The existence of intermolecular interactions and hydrogen bonding between SHP and SPI was founded by infrared spectroscopy and scanning electron microscopy. It was confirmed by 7d storage experiments that the storage stability of the emulsion gel was enhanced with the increase of SHP addition, and the best stability of the emulsion gel was achieved when the SHP addition was 0.45%. This study aimed to provide the theoretical basis for the development and application of SHP in food emulsion gels.