漆酶对小麦面团冻藏期间品质的影响研究

Effects of laccase on the quality of wheat dough during storage

采用粉质仪、流变仪、质构仪及扫描电子显微镜系统研究了漆酶对小麦面团冻藏(-18℃分别冻藏0、7、14、21d及28d)过程中的流变学特性、拉伸特性及微观结构变化的影响规律。结果表明:漆酶可以改善面团的流变学特性,从而提高面团的冻藏稳定性。在面团冻藏过程中,漆酶添加量大于20nkat/g组的储能模量G'、最大拉伸阻力(Rmax)明显高于4nkat/g组及0nkat/g对照组;拉伸结果显示:漆酶可有效增加小麦面团的Rmax值,但对面团的延伸性(Ex)有削弱作用;扫描电镜结果显示:经过28d的冻藏,添加了漆酶的面团其面筋网络较对照组的立体感、连续性更好。漆酶能有效减弱冻藏过程对面筋网络结构的破坏,提高面团的稳定性。研究可为漆酶在面制品中的应用提供理论依据和指导。

The effects of laccase (LAC) on the rheological properties,extensographical properties and microstructure of wheat dough during frozen storage (-18 ℃ for 28 days) were investigated by farinograph,rheometer,texture analyzer and scanning electron microscopy (SEM).The measurements were made at 0,7,14,21 d and 28 days,respectively.The results showed that laccase could improve the rheological properties and stability of dough during frozen storage.With the addition of 20 nkat/g laccase, the storage modulus (G') and the maximum resistance to extension (Rmax) of the dough were significantly higher than those of the samples containing 4 nkat/g laccase and the control group during frozen storage. The results from texture analyzer illustrated that laccase could effectively increase the Rmax value of wheat dough,but with a decrease in the extensibility (Ex) of the dough.Scanning electron microscopy analysis revealed that the dough gluten network with laccase was kept in a good three-dimensional sense and better in continuity after frozen storage for 28 days.These results indicated that laccase could effectively weaken the destruction of gluten network resulting from frozen storage,and improve the frozen storage stability of dough.This study provides a theoretical basis and guidance for the application of laccase in flour products.