Effect Of Wheat Source (Drought And Waterlogging) On The Physical And Chemical Properties Of Wheat Flour And The Quality Of Steamed Bread

Wheat is easily effected by environmental factors,drought and waterlogging treatment will limit the nutrient absorption of wheat and reduce the yield and quality of wheat.In this thesis,different sources of wheat were used as raw materials for milling,and the effects of different treatments on the particle size distribution,gelatinization characteristics and rheological properties of wheat flour were studied.On this basis,the southern steamed buns were made from different sources of wheat flour and their quality was analyzed,in order to clarify the effects of different treatments on the physical and chemical properties,rheological properties of dough and processing quality of wheat flour.The quality difference between wheat flour treated by drought and flood and normal wheat flour was compared.The basic components of wheat grains were studied and the flour production experiment was carried out.The results showed that the starch content was slightly reduced by drought and flood treatment.Drought treatment resulted in the decrease of grain protein content to10.0% and yield to 55.0%.The effects of drought and waterlogging treatment on the particle size distribution,pasting properties,thermal properties,solubility,swelling power and solvent retention capacity of wheat flour were investigated by particle size analyzer,rapid visco-analyzer(RVA)and differential scanning calorimeter(DSC).The results showed that the particle size of wheat flour was increased by waterlogging treatment.The peak viscosity,trough viscosity,disintegration value,final viscosity and regeneration value of wheat affected by 4 days of waterlogging were the same as that of wheat subjected to waterlogging for 8 days.The number of waterlogging days was the same,the waterlogging depth decreased,the gelatinization temperature of wheat flour increased,and the gelatinization enthalpy value decreased.The waterlogging depth is the same,the shorter the waterlogging days,the greater the solubility expansion;The comprehensive properties of wheat flour were good after 0 cm and 4 days.The gluten macromer content(GMP)of wheat subjected to 4 days of waterlogging was higher than that of 8 days of waterlogging.Drought treatment led to a decrease in the particle size of wheat flour;The peak viscosity and disintegration value of drought-affected wheat flour were high.During the drought period,the gelatinization temperature of wheat flour increased,and the enthalpy of gelatinization decreased.The solubility and expansion of wheat flour during the pulling pregnancy period are large;The comprehensive properties of arid wheat flour were poor.The GMP content of wheat flour was reduced by drought treatment.The rheological characteristics of dough were studied by Mixolab mixer,tensile meter and rheometer,and it was shown that the water absorption rate of dough was increased,the stabilization time was reduced,and the regeneration value was reduced by waterlogging treatment.The shorter the number of days of waterlogging,the greater the tensile resistance and stretching length of the dough;At 0 cm of waterlogging,the storage modulus(G’)and loss modulus(G’’)of 4 d wheat dough were greater than those of the control,and the loss tangent(tan δ)<1,at which time the dough had good viscoelasticity.The water absorption rate of dry wheat dough decreased,the stabilization time increased,and the regeneration value decreased.The tensile resistance and length of dough gradually decreased with the change of dry wheat growth period.The G’ and G’’ values of dough during the pulling period of pregnancy increased,the tan δ value decreased,and the viscoelasticity was good.In addition,the wet gluten index(P < 0.05)was significantly increased by drought treatment.At the same time,the free sulfhydryl content of dough(P < 0.05)was significantly increased by drought and flood treatment.Drought and waterlogging treatment will reduce the quality of steamed buns,and the quality of steamed buns was the best when waterlogged 0 cm,4 days and drought steamed buns during pregnancy,and the volume of steamed buns at this time was 2.88 m L/g and 2.63 m L/g,respectively,the color was whiter,the stomatal distribution was delicate and uniform,the porosity was 25.20% and 24.09%,the steamed buns were soft and the anti-aging characteristics were better.