【作者】 王沛； 邹敏； 杨润强； 姜东； 顾振新；

【Author】 Wang Pei;Zou Min;Yang Runqiang;Jiang Dong;Gu Zhenxin;College of Food Science and Technology,Nanjing Agricultural University;College of Agriculture,Nanjing Agricultural University;

【机构】 南京农业大学食品科技学院； 南京农业大学农学院；

【摘要】 面筋蛋白劣变是冷冻面团品质下降的主要因素,已有研究虽从冻藏阶段阐明面筋蛋白品质劣变机制,但对熟制阶段冻藏面筋蛋白在热聚集作用下的品质变化缺乏深入研究。本文研究不同加热温度下面筋蛋白分子量、亚基组成、非共价作用力、二级结构、表面疏水性和微观结构的变化,旨在揭示热诱导的冻藏面筋蛋白的解折叠和聚集行为的变化机制。结果表明,冻藏面筋蛋白的醇溶蛋白和谷蛋白的热聚集能力显著下降,其中冻藏面筋蛋白中谷蛋白单体对加热敏感性最高,而γ-醇溶蛋白的热敏感性最低。冻藏面筋蛋白在初始加热阶段的解折叠过程受到明显抑制:加热过程中冻藏面筋蛋白中有序的α-螺旋结构高于未冻藏面筋蛋白,且表面疏水基团的暴露程度较未冻藏面筋蛋白低。微观结构分析表明,冻藏面筋蛋白网络在50℃时收缩程度更大,当温度超过70℃时,其进一步聚集形成更为厚实的孔壁结构。本研究可完善冻藏面筋蛋白的劣变机理,为有效调控冷冻面团品质提供更全面的理论依据。更多还原

【Abstract】 Gluten deterioration is the main factor for the degraded quality of frozen dough.Previous studies comprehensively elucidated the degradation mechanism of gluten during frozen storage,however,the subsequent changes of frozen-stored gluten properties remains largely unelucidated.The current study comparatively investigated the effects of heating on the unfolding and polymerization process of frozen-stored gluten from molecular weight,subunit composition,non-covalent interactions,secondary structure,surface hydrophobicity and microstructure.Results showed that the polymerization ability of both gliadin and glutenin in the frozen-stored gluten were dramatically reduced.Glutenin monomers were more sensitive,while the γ-gliadins were less sensitive to polymerize upon heating for frozen gluten.Frozen storage could impede the unfolding process at the initial heating stage for frozen gluten:the ordered α-helices in frozen gluten were significantly higher than that of fresh gluten during heat treatment,and the surface hydrophobic groups were more buried than fresh gluten.The microstructural analysis suggested that the ruptured frozen gluten network was more sensitive to shrink during the initial heating at 50 ℃ and further formed denser and thicker pore walls when the temperature exceeded 70 ℃.This study may consummate the deterioration theory of frozen gluten quality from both freezing and heating stages,and thus providing a more comprehensive theoretical basis for the effective preservation of frozen dough quality.更多还原