背景:传统的大豆蛋白凝胶产品,如豆腐,由硫酸钙或氯化镁形成,具有较差的质地和保水能力。大豆大豆球蛋白(SG)是影响大豆蛋白凝胶化的主要成分,可与多糖交联,如甜菜果胶(SBP),并且可以通过改变系统因素来修改(例如,pH)以改善凝胶的性能。采用漆酶交联和热处理在弱酸性条件下制备SG/SBP复合双网络凝胶。研究了SG的结构变化和复杂凝胶的性质。
结果:SG在pH5.0时暴露了更多的疏水基团和游离巯基。在漆酶交联的作用下,SBP可以促进SG三级结构的展开。SG/SBP复合凝胶含有46.77%的β-倍含量,具有硬度290.86g的良好胶凝性能,粘附性26.87,在pH5.0时的弹性96.70mm。T22弛豫时间的峰值最高,MRI显示凝胶具有均匀的水分布。扫描电子显微镜(SEM)和共聚焦扫描激光显微镜(CLSM)显示SG/SBP复合网络结构均匀,孔壁较厚,内部含有丝状结构。
结论:SG/SBP复合网络凝胶具有良好的保水性,pH5.0时的流变和质地特性。通过与漆酶交联的多糖结合并调节溶液的pH,可以改善大豆蛋白凝胶的性能。本文受版权保护。保留所有权利。
BACKGROUND: Traditional soy protein gel products such as tofu, formed from calcium sulfate or magnesium chloride, have poor textural properties and water retention capacity. Soy glycinin (SG) is the main component affecting the gelation of soy protein and can be cross-linked with polysaccharides, such as sugar beet pectin (SBP), and can be modified by changing system factors (e.g., pH) to improve the gel\'s properties. Soy glycinin/sugar beet pectin (SG/SBP) complex double network gels were prepared under weakly acidic conditions using laccase cross-linking and heat treatment. The structural changes in SG and the properties of complex gels were investigated.
RESULTS: Soy glycinin exposed more hydrophobic groups and free sulfhydryl groups at pH 5.0. Under the action of laccase cross-linking, SBP could promote the unfolding of SG tertiary structures. The SG/SBP complex gels contained 46.77% β-fold content and had good gelling properties in terms of hardness 290.86 g, adhesiveness 26.87, and springiness 96.70 mm at pH 5.0. The T22 relaxation time had the highest peak, and magnetic resonance imaging (MRI) showed that the gel had even water distribution. Scanning electron microscopy (SEM) and confocal scanning laser microscopy (CLSM) indicated that the SG/SBP complex network structure was uniform, and the pore walls were thicker and contained filamentous structures.
CONCLUSIONS: Soy glycinin/ sugar beet pectin complex network gels have good water-holding, rheological, and textural properties at pH 5.0. The properties of soy protein gels can be improved by binding to polysaccharides, with laccase cross-linked, and adjusting the pH of the solution. © 2022 Society of Chemical Industry.