[关键词]
[摘要]
本研究以从稀到浓的小麦面筋蛋白溶液为对象,对其进行湿热脱酰胺处理,分析了湿热脱酰胺改性过程中当蛋白浓度从极稀到亚浓变化时,小麦面筋蛋白分子结构和聚集态变化对脱酰胺程度的影响。实验结果表明:小麦面筋蛋白脱酰胺程度、水解度和Zeta电位随着蛋白原始聚集态的增大而显著降低,且脱酰胺程度和水解度随小麦面筋蛋白原始聚集态变化呈现线性相关性。小麦面筋蛋白分子内作用力随着蛋白原始聚集态的增强而显著增大,红移程度则减小。小麦面筋蛋白分子内部非共价键包括疏水键和氢键在蛋白分子中起主导作用,二硫键作用微小。以上结果说明小麦面筋蛋白聚集形态与湿热有机弱酸脱酰胺速率具有较强的相互关系,蛋白原始的聚集形态是决定分子结构伸展程度和脱酰胺改变趋势的最重要因素。
[Key word]
[Abstract]
Abstract A series of diluted and concentrated wheat gluten solutions were used in this experiment to carry out deamidation under moist heat. During the moist-heat-induced denaturation, the effect of molecular structure and aggregation state of wheat gluten on the degree of deamidation was analyzed. The results showed that the degree of deamidation, degree of hydrolysis, and zeta potential significantly decreased with increasing aggregation of native wheat gluten. Additionally, both degree of deamidation and hydrolysis had a good linear relationship with the changes in the aggregation state of wheat gluten. The intermolecular force of wheat gluten significantly increased with increasing aggregation of native wheat gluten, and the red shift became smaller. The intermolecular noncovalent bonds, including hydrogen bonding and hydrophobic interaction, were the main molecular forces for the aggregated wheat gluten; disulfide bonds had a minimal effect. These results demonstrated that the aggregation state of native wheat gluten is closely related to the rate of wheat gluten deamidation via moist heat treatment using food-grade organic acid. The aggregation state of native wheat gluten is the most important factor for the unfolding degree of protein molecules and aggregation trends of wheat gluten.
[中图分类号]
[基金项目]
国家自然科学青年基金项目资助(31201287)