麦麸酚酸对面团及面筋蛋白理化性质的影响

Effects of Wheat Bran Phenolic Acids on Physicochemical Properties of Dough and Gluten Protein

选取4种酚酸【咖啡酸(CA)、对香豆酸(p-CA)、丁香酸(SA)和没食子酸(GA)】添加到高筋小麦粉中,探讨小分子酚酸物质对面团理化特性的影响。采用快速黏度仪测定面团的糊化性质,Mixolab测定面团的热机械学特性,流变仪测定面筋蛋白的流变特性,差示扫描量热法(DSC)和热重分析(TGA)测定面筋蛋白的热力学性质。结果表明:在p-CA添加量为0.1%时有利于面团保持较高的终止黏度(4399 cp),添加CA和SA能抑制淀粉的老化。CA、p-CA、GA、SA可以显著提高(P<0.05)面团的吸水率,减少稳定时间,其中添加0.3%的GA时,面团吸水率最高为63.08%。然而,4种酚酸的添加也会导致淀粉分子的重新排列被破坏,从而导致凝胶程度增加。在添加CA、p-CA、GA、SA后,总体上面筋蛋白黏弹性提高,且除p-CA以外,其余3种酚酸均会导致面筋蛋白的热稳定性降低并使面筋强度减弱。最后,面团的微观结构图还表明CA、pCA、GA、SA的添加均使面筋蛋白原本均匀致密的微观结构被破坏,并且破坏程度随酚酸添加量的增加而增大。

Four phenolic acids[caffeic acid(CA),p-coumaric acid(p-CA),syringic acid(SA),and gallic acid(GA)]were selected and added to high-gluten wheat flour to investigate the effects of small molecule phenolic substances on the physicochemical properties of dough.Rapid viscometer was used to determine the pasting properties of the dough,Mixolab to determine the thermo-mechanical properties of the dough,rheometer to determine the rheological properties of the gluten proteins,and differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA)to determine the thermodynamic properties of the gluten proteins.The results showed that the addition of p-CA at 0.1%was favorable for the dough to maintain a high termination viscosity(4399 cp),and the addition of CA and SA inhibited the aging of starch.CA,p-CA,GA,and SA could significantly increase(P<0.05)the water absorption of dough and reduce the stabilization time,among which the highest water absorption of 63.08%was observed when 0.3%of GA was added.However,the addition of the four phenolic acids also led to the disruption of the rearrangement of starch molecules,which resulted in an increase in the degree of gelation.The overall viscoelasticity of gluten proteins was increased by the addition of CA,p-CA,GA,and SA,and all three phenolic acids,except p-CA,resulted in a decrease in the thermal stability of gluten proteins and a weakening of gluten strength.Finally,the microstructures of the doughs also showed that the addition of CA,p-CA,GA,and SA disrupted the originally homogeneous and dense microstructure of gluten proteins,and the extent of the disruption increased with the increase in the amount of phenolic acid added.