Research On The Formation Mechanism And Improvement Strategy Of Chinese Steamed Bread Quality Based On The Characteristic Components Of Wheat Flour

Wheat starch and gluten protein are the characteristic components of wheat flour,which have significant influence on the processing and storage quality of Chinese steamed bread.However,the effects of wheat starch and gluten on the formation mechanism and staling mechanism of Chinese steamed bread quality have not been fully revealed.Therefore,the influence of the difference in wheat gluten and starch content on the quality of Chinese steamed bread was studied,different temperature storage was used to research the staling mechanism of steamed bread,and quality improvement technology based on carboxymethyl cellulose was developed in this paper.It provides theoretical support for enriching the evaluation standards of wheat flour for Chinese steamed bread and improving the storage stability of Chinese steamed bread.The main results are as follows:1.Excluding the interference of other wheat components on the quality of Chinese steamed bread,the influence mechanism of the gluten-starch ratio on the quality of Chinese steamed bread was studied.With the increase of gluten-starch ratio from 10:90to 25:75,the sensory score of steamed bread increased from 69.0 to 81.8,and the hardness gradually decreased from 608.33 to 298.26.Besides,the flavor of steamed bread with different gluten ratio could be distinguished by principal component analysis.With the increase of the gluten-starch ratio,the?-sheet of the protein secondary structure increased from 40.05%to 41.99%,and the crystallinity of starch decreased from 9.95%to 2.03%.Nuclear magnetic resonance results showed that the water holding capacity and the uniformity of water distribution of steamed bread were improved.The results showed that the quality of steamed bread with different gluten-starch ratio was significantly different(p<0.05).2.Based on the various characteristics of Chinese steamed bread,the staling mechanism of Chinese steamed bread affected by temperature was studied.At 25?,4?and-20?,the springiness of steamed bread fluctuated around 0.9,0.8 and 0.94respectively,and the starch recrystallization degree was 2.26%,5.06%and 1.49%respectively.The protein secondary structure changed the most at 25?,?-sheet content gradually increased from 44%to 48%.But at 4?and-20?,the protein secondary structure changed little,and?-sheet content fluctuated around 48%.At 4?,the water migration was fast and the water holding capacity of gluten decreased the fastest,followed by 25?.However,the water migration of Chinese steamed bread was the slowest at-20?.The results showed that the staling rate of steamed bread was different at different temperatures,and the staling rate of Chinese steamed bread was 4?>25?>-20?.3.The quality improvement technology of frozen steamed bread based on carboxymethyl cellulose was established,and the improvement of Chinese steamed bread quality with different carboxymethyl cellulose addition and degree of substitution was studied.The protein secondary structure of steamed bread with carboxymethyl cellulose remained basically unchanged during the first 15 days of frozen storage,and the water migrated from T₂₂ to T₂₁,which had obvious advantages in the stability of frozen storage quality.At the late 15 days of frozen storage,the?-sheet content gradually decreased to below 47%,the moisture migrated from T₂₁ to T₂₂,and the quality of steamed bread decreased.The addition of carboxymethyl cellulose with degree of substitution of 1.2 delayed the recrystallization of starch,reduced the damage of structure during frozen storage,and reduced the water mobility.Moreover,2%CMC increased the specific volume and springiness of steamed bread,and improved the water holding capacity of gluten.It showed that the frozen storage stability of steamed bread was the best when the addition of carboxymethyl cellulose with a degree of substitution of 1.2 was 2%.The above research results showed that gluten and starch affected the stability of gluten and gelatinization of starch by competing for water,and then affected the formation mechanism and staling process of Chinese steamed bread.Besides,freezing and carboxymethyl cellulose(2%addition,1.2 degree of substitution)could delay the staling of steamed bread and improve the quality of Chinese steamed bread to a certain extent.