Development And Research Of JiaoZi Self-fermentable Flour

Self-fermentable flour is a convenient food for making steamed bread,and its taste and flavor are one of its disadvantages.Yeast-made steamed buns are full of flavor,good taste,and flexible,but because of the complicated manufacturing process,they cannot guarantee the consistency of the production.Adding yeast as a food leavening agent to self-fermentable flour,there are few studies in China.First,we screened different ferments and chemical leavening agents.Through comprehensive analysis of enzyme activity,total number of colonies volatile substances,and steamed bread indicators,we found out more suitable fermented leavens and leavening agents.Secondly,the formula of JiaoZi self-fermentable flour was optimized by response surface method,and the process of making JiaoZi self-fermentable flour by orthogonal optimization was made.At the same time,the dough characteristics and volatile substances of JiaoZi self-fermentable flour were studied,and then JiaoZi self-fermentable flour made from JiaoZi self-fermentable steamed bread was compared with that of traditional JiaoZi steamed bread.Finally,the storage conditions of y JiaoZi self-fermentable flour were studied.The aim is to develop a JiaoZi self-fermentable flour with traditional JiaoZi steamed bun flavor,and provide a certain theoretical basis for actual production.The main findings are as follows:Firstly,four different ferments were screened,and the total number of colonies,amylase and protease,volatile matter analysis,steamed bread volume,hardness,whiteness,and senses were comprehensively analyzed.The study found that fermenter 3 was significantly better than the other three fermenters in the three indexes of amylase activity,protease activity,and the total number of bacterial colonies(p <0.05),and the types and contents of volatile substances were also greater than those of the other three ferments.In the sensory score of steamed buns,there was no significant difference(p <0.05)from fermentor 2 but better than the other two.Comprehensive analysis selected fermenter 3 as the biological leavening agent.Four different combinations of leavening agents were screened,and the whiteness,hardness,specific volume and sensory characteristics of the steamed bread were analyzed.The research and comparison of glucose lactone were better than the other three,and glucose lactone and sodium bicarbonate were selected as chemical leavening agents.Using single factor test and Box-Behnken test design,the optimal formula of JiaoZi self-fermentable flour was obtained: 0.86% of yeast,0.50% of yeast,and 1.20% of chemical leavening agent.Under this optimized condition,the theoretical value of the sensory score of steamed buns with the best formula was 88.2 points.Then,comprehensive analysis was performed on the JiaoZi self-fermentable flour steamed bread dough based on the gelatinization viscosity characteristics,flour volatile substances,dough rheology characteristics,fermentation rheology characteristics,amino acid composition,and dough volatile substances.The study found that JiaoZi self-fermentable flour was significantly better than the other four kinds of commercial spontaneous flour dough in terms of gelatinization characteristics and powder quality characteristics(p <0.05).Experiments show that compared with the other four kinds of spontaneous powder,JiaoZi self-fermentable flour is more suitable for making steamed buns.Determination of volatile matter in flour,analysis of amino acid composition of dough,and analysis of volatile matter in dough show that JiaoZi self-fermentable flour steamed bun has more flavor content and quantity than the other four kinds of spontaneous flour.It can be said that JiaoZi self-fermentable flour is indeed a flavored spontaneous powder.Next,the single-factor test and orthogonal test design were used to obtain the best technological conditions for the JiaoZi self-fermentable flour: the amount of water added was 48%,the time for noodles was 12 minutes,the number of times for noodle pressing was 12 times,and the time for proofing was 30 minutes.Compared with other spontaneous powder buns,the JiaoZi self-fermentable flour steamed buns have a sweeter taste,are chewy and have better recovery.At the same time,by using SDE simultaneous distillation and extraction,and using gas-mass spectrometry technology to analyze and compare volatile substances in different spontaneous flour buns.JiaoZi self-fermentable flour steamed buns reached a maximum of 73 types,and the aromatic compound content reached a maximum of 0.0081 μg / g.Different spontaneous flour buns were found in the amount and relative content of volatile substances in the production process.The relative content of alcohols was the highest in the dough,and the microorganisms produced a large amount of alcohols during the fermentation process.After that,the volatile substances of yeast fermented buns and fermented yeast buns and yeast fermented buns were compared.The JiaoZi self-fermentable flour steamed buns had more flavor substances than the yeast fermented buns.The relative content of the compounds is close,so to a certain extent it can be said that the flavor of JiaoZi self-fermentable flour steamed bun powder is better than that of primary fermentation steamed bun and has a certain traditional JiaoZi steamed bread flavor.Lastly,studies on the effects of three types of packaging,vacuum packaging,non-woven packaging,and sealed packaging,on the storage quality of JiaoZi self-fermentable flour,found that: non-woven packaging has good air permeability,faster yeast inactivation,and shorter shelf life.From the fatty acid value and steamed bread index,no significant difference was found between vacuum packaging and sealed packaging(p <0.05).From the perspective of operability,sealed packaging was selected,but the shelf life was shorter only 80 days.On this basis,its moisture content was reduced to extend the shelf life,and its original moisture content was 13.8%.Then,the effects of five moisture contents of 9.3-13.3% on the shelf life of JiaoZi self-fermentable flour were studied.Wheat flour falling number meter,whiteness meter,fatty acid measurement,dough fermentation characteristics measurement,flour quality index measurement,steamed bread whiteness,hardness,sensory index.It was found that during storage,the falling value of wheat flour generally increased,and the higher the water content,the faster the rise;the whiteness value experienced a process of first rising and then falling,but the overall change trend was not obvious;the fatty acid value is the national standard physicochemical limit.The overall value increases,the higher the moisture content,the faster the rise;the fermentation characteristics of the dough is the best indicator of the shelf life of the JiaoZi self-fermentable flour,and the steamed bread index can correspond to it.13.3% of fermented spontaneous steamed bun powder loses its fertility and expires in 3 months,12.2% loses its fertility and expires in 4 months,11.2% expires in 5 months,and 9.3% and 10.3% still have fermentation when stored for 6 months Power,but the fatty acid value exceeds the national standard value at 7 months,so the JiaoZi self-fermentable flour can reduce the moisture content to 10.3% to extend the shelf life to 6 months.