Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, 100083, China.
The Experimental High School Affiliated to Beijing Normal University, Beijing, 100032, China.
Biomaterials. 2022 Jan;280:121275. doi: 10.1016/j.biomaterials.2021.121275. Epub 2021 Nov 24.
Gluten network formed by oxidation of glutenin sulfhydryl groups is the determinant of dough rheological properties, while chemical reagents including oxidants and reductants are both used as dough rheology improvers under different circumstances. This study compares the impact of sodium metabisulfite (SMBS) and azodicarbonamide (ADA), as the representative reductive and oxidative dough improvers, at series of concentrations that offer or remove the same number of electrons form dough, respectively. The alveographic characterization, protein distribution and glutenin composition analysis, and free sulfhydryl measurement were performed on dough containing redox equivalent SMBS or ADA. Finally, at each optimal concentration, the dough protein network was analyzed with confocal microscopy. Results showed that SMBS increased the free sulfhydryl content, loosened the microstructure of gluten network, and thus enhanced dough extensibility. ADA reduced the free sulfhydryl content, compacted the dough microstructure, thus enhanced the tenacity and baking strength of dough. It is therefore proposed that the reductants reduce disulfide bonds in gluten network and renders the formation of one-dimensional gluten network while oxidants promote the disulfide linkage and formation of three-dimensional gluten network. This study offers a theoretic foundation of differentiating dough rheology improvers for their specified application.
由谷朊硫醇基团氧化形成的谷朊网络是面团流变性的决定因素，而包括氧化剂和还原剂在内的化学试剂在不同情况下都被用作面团流变性改良剂。本研究比较了亚硫酸氢钠（SMBS）和偶氮二甲酰胺（ADA）作为代表性的还原和氧化面团改良剂的影响，它们分别在提供或去除相同数量电子的一系列浓度下作用于面团。对含有氧化还原当量 SMBS 或 ADA 的面团进行了粉质图特性、蛋白质分布和谷朊组成分析以及游离巯基测量。最后，在每个最佳浓度下，使用共聚焦显微镜分析面团蛋白网络。结果表明，SMBS 增加了游离巯基含量，使面筋网络的微观结构变松，从而增强了面团的拉伸性。ADA 降低了游离巯基的含量，使面团的微观结构更加紧密，从而增强了面团的韧性和烘焙强度。因此，可以提出还原剂还原面筋网络中的二硫键，并形成一维面筋网络，而氧化剂促进二硫键的形成和三维面筋网络的形成。本研究为区分面团流变性改良剂及其特定应用提供了理论基础。
