Effect Of Ferulic Acid On The Characteristics Of Whole Wheat Dough And The Quality Of Whole Wheat Steamed Bread

Wheat bran is the key factor that reduces the processing characteristics of whole wheat dough and degrades the taste of whole wheat food.Degrading wheat bran to alleviate the negative effect of dietary fiber on whole wheat dough is the main method to improve the quality of whole wheat food.However,the effects of free ferulic acid(FA)and other phenolic acids released during the degradation of wheat bran on the characteristics of whole wheat dough and the quality of whole wheat food are still unclear.Therefore,this paper studied the improvement effect of FA,a key phenolic acid in wheat bran,on the rheological characteristics of whole wheat dough and its influence on the quality of whole wheat steamed bread,and discussed the regulation effect of FA on the aggregation behavior of gluten,so as to provide support basis for enriching the technical means of efficient improvement of whole wheat food quality.The main conclusions of this paper are summarized as follows:1.Previous laboratory studies had found that the co-fermentation technology of Lactobacillus plantarum LB-1 and yeast to degrade wheat bran can significantly improve the rheological properties of whole wheat dough,in which free FA played a crucial role.Therefore,this paper studied the effects of adding free FA on the rheological and texture properties of whole wheat dough.The results showed that FA increased the extensibility of whole wheat dough by 9.68% and decreased the hardness by 18.63% compared with whole wheat dough co-fermented with LB-1 and yeast.The tensile resistance of whole wheat dough increased by 14.28% after adding FA compared with common yeast fermented whole wheat dough,and the improvement effects of adding FA on viscoelasticity,creep recovery ability and water holding capacity of whole wheat dough were more similar to those of co-fermented whole wheat dough,indicating that adding FA could effectively replace co-fermented technology to improve the rheological and texture properties of whole wheat dough.2.The effects of different FA supplemental proportions on texture and quality of whole wheat steamed bread were studied.The results showed that the addition of 0.5%FA reduced weakening degree of gluten and the fibrous gluten skeleton structure and membrane gluten in whole wheat dough increased significantly with better continuity compared with the control group,so that starch granules could be effectively wrapped in membrane gluten.Moreover,the addition of 0.5% FA improved the water holding capacity of whole wheat dough and effectively reduced the water loss in the core of whole wheat steamed bread during storage.The specific volume of whole wheat steamed bread was increased by 20.26% and the internal structure,elasticity,cohesiveness and other textural characteristics of whole wheat steamed bread were improved by 0.5% FA.However,the addition of high dose of 1%-1.5% FA had a negative effect on the gluten network structure,specific volume and texture characteristics of whole wheat steamed bread.3.The effects of different FA supplemental proportions on the structure and aggregation behavior of gliadin,glutenin and gluten were studied in an attempt to reveal the potential mechanism of FA influence on texture and quality of whole wheat steamed bread.The results showed that 0.5% FA decreased the content of free sulfhydryl group of glutenin and gluten,and increased the average grain size of gluten.the β-fold content increased by 20.40% compared with the control group when 0.5% FA was added.The high-dose FA significantly reduced the bimodal ratio of glutenin tyrosine and increased the polarity of the microenvironment around tryptophan residues,which promoted the disordered structure formation of gluten and was not conducive to the formation of stable dough network structure.SDS-PAGE showed that 0.5% FA promoted the formation of high molecular weight protein by crosslinking and aggregation of low molecular weight protein components.It was confirmed that 0.5% FA promoted the cross-linking aggregation behavior of gluten molecules by atomic force microscope analysis.High dose FA made the distribution of gluten protein aggregates uneven and the gluten network structure disordered and loose,which was not conducive to the formation of continuous and stable dough.