A Study On Bread Premixed Flour

Bread premixed flour means to premix all the raw materials (except individual raw materials) according to the formula to make bread.This project studies a kind of bread premixed flour by adding only water to make bread.By adding powdered oil,yeast and the composite bread improvers of delaying bread staling,getting the bread premixed flour,it could be made into bread by adding only water.The main research contents as follows:By adding a certain proportion of powdered oil into the bread flour,in virtue of Brabender,testing the rheological characters of dough, determining that adding 4%-8% powdered oil,the rheological characters of dough are better.By adding 3% shortening as the blank control group, with adding 4%,6% and 8% powdered oil to do the control experiment,in virtue of sensory evaluation and texture analysis,after adding 6% powered oil,a good sensory assessment and texture of bread could be obtained.The storage results showed that,the bread premixed flour of adding 1.2% yeast,at the preservation condition of 25℃airproof for 30d,the specific volume of bread is 4.18 cm3 / g,which is smaller than the blank control group of 4.30 cm3 / g,so it needs to stabilize the yeast vitality.On that basis,adding xanthan gum and Monoglyceride into the bread flour respectively,in virtue of Brabender,testing the rheological characters of dough,determining that adding xanthan gum 0.3%-0.9% and adding Monoglyceride 0.4%-1.2%,the rheological characters of dough are better;In virtue of Land value detector , it determines that addingα-amylase 0.0003% - 0.0009% is better.According to the orthogonal test,carrying on the bread experiment,at room temperature preservation 2h,24h and 72h,test breads are carried on Texture Analyzer test.Orthogonal Results:xanthan gum 0.6%,Monoglyceride 1.2% andα-amylase 0.0006%.It studies on stabilizing the yeast vitality,adding yeast 2.0%,on that basis,adding yeast nutritive salt NH4Cl,MgSO4,CaSO4 and KH2PO4,according to the orthogonal test,in virtue of cylinder method.Orthogonal results:NH4Cl 0.04%,MgSO4 0.08%,CaSO4 0.10% and KH2PO4 0.09%.On the basis of the orthogonal test,carrying on F3 Rheofermentometer experiment,results show:after adding nutritive salt, Hm 67.2mm,H'm 77.3mm,CO2 1189ml,the blank group Hm 60.6mm,H'm 75.5 mm,CO2 1121 ml.After adding nutrients,at 25℃storage 30d,Hm 59.4 mm,H'm 74.2 mm,CO2 1108 ml.The blank control group,at 25℃storage 30d,Hm 55.6 mm,H'm 71.8 mm,CO2 1024 ml.After adding yeast nutritive salt,yeast vitality can be stabilized better.Based on the above findings,I prepare a kind of bread premixed flour by adding only water to make bread,after 25℃and 30℃airproof storage 30d,experiment results show that the specific volume of the blank group is 4.90 cm3/g,25℃and 30℃airproof storage for 30 days,the specific volume are 4.75 cm3 / g and 4.55 cm3 / g.Compared to the blank control group,25℃storage,the test breads are preserved for 72h at room temperature,the breads hardness are 1167.917 g,are better than the blank group 1273.332 g.