Study On The Relationship Between Moisture Distribution And Texture Of Frozen Dough And Development A Frozen Dough Improver

Baked products such as bread produced by frozen dough have the advantages of instant roasting,fresh flavor,scale production,and low production cost,and can enrich product types and ensure product quality stability.Therefore,frozen dough technology is a trend in the development of the baking industry.The complex physical and chemical changes that occur during the freezing process of the dough affect the moisture distribution of the dough,the gas production of the yeast,and the gluten network structure.These changes ultimately affect the color,aroma,taste and shape of the product.After adding the improver will reduce or eliminate the effects of this change on product quality.It is well known that trehalose has a protective effect on organisms(yeast)during the freezing process,Most of the frozen dough improvers on the market are based on the addition of trehalose to improve the gas production performance of the dough during the freezing process,but in general,these improvers did not achieve the desired effect,mainly because the dough structure was not improved during freezing,And the moisture content,moisture state and water distribution in the dough have a great influence on the dough structure.In this paper,the effects of water-holding of locust bean gum,water-retaining of sodium hexaphosphate and trehalose on the moisture distribution of frozen dough were studied,and the mechanism was also discussed.The effects of emulsifiers,enzymes and antioxidants on flour and dough rheology were also studied;Finally,locust bean gum,sodium hexametaphosphate,trehalose,emulsifier,enzyme preparation,etc.were compounded to form a frozen dough improver,with a transport cycle as a freeze cycle,the effect of the improver was verified from four aspects: farinograph,flour gelatinization,dough rheology and bread quality.The results showed that the frozen dough improver could improve the structure and quality of frozen dough.The frozen dough improver was produced and sold in a food company in Guangdong.The main research contents and conclusions are as follows:1.The addition of colloids to the flour affects its water absorption and moisture state.The effects of locust bean gum with good water retention properties on the gelatinization properties of flour were studied.After the dough was made,the moisture distribution,dough microstructure and fermentation speed of the dough were measured at different times.At the same time,the texture structure and texture characteristics of bread in different periods were also studied.The results showed that the rate of decrease of the proportion of frozen dough combined with water after adding locust bean gum was delayed.The addition of locust bean gum protected the network structure of gluten protein,maintained the arrangement of starch granules and stabilized the speed of dough fermentation.The rate of deterioration of the quality of the frozen dough and its baked bread during storage is delayed,which is consistent with the moisture distribution of thedough.It can be seen that the quality of the frozen dough can be predicted and analyzed by the moisture distribution state of the dough.2.Sodium hexametaphosphate has strong water retention.It is used in baked foods to affect the moisture distribution in the dough.This chapter mainly studies the water distribution,microstructure and fermentation speed of frozen dough by adding sodium hexametaphosphate and trehalose,and the effect of the texture of the bread after baking.The results showed that sodium hexametaphosphate and trehalose delayed the rate of decrease of bound water and the rate of increase of freezeable water,which made the moisture distribution of the frozen dough more uniform,the microstructure of the dough was more stable,and the elasticity of the frozen dough bread greater and the hardness lower,the taste softer.So the interaction between sodium hexametaphosphate and trehalose can effectively maintain the quality of the frozen dough.3.The moisture distribution has a great influence on the quality of the product formed by the frozen dough.In addition,the addition of emulsifiers,enzyme preparations and antioxidants will also affect the dough structure and affect the quality of the final product.Studies have shown that sodium stearoyl lactylate,fungal alpha-amylase and ascorbic acid synergistically improve the flour properties and rheological properties of flour.A frozen dough improver was prepared by using all the above materials,and the results showed that the frozen dough improver has obvious effects on reducing the rate of deterioration of the frozen dough and the frozen dough bread.When the addition amount of the frozen dough improver is 1% or 2%,the water absorption rate and the stabilization time of the flour are significantly increased,and the degree of weakening is remarkably reduced;the gelatinization viscosity of the flour is generally decreased after the addition of the frozen dough improver,the degree is 3%>2%>1%;as the amount of frozen dough improver increases,the attenuation value of the dough,the elastic modulus(G’)and viscous modulus(G’’)all gradually decreased,the stress relaxation characteristics are more stable;the frozen dough improver delays the increase rate of the dough tangent angle;when the amount of the frozen dough improver is 1%,the pH and hardness of the bread are smaller,indicating that the amount of the dough improver added is 1%,a better improvement effect can be exhibited.