Conditioning Method For Characteristics Of Wheat Flour And The Change Of Microorganism

This experiment carried out different tempering technology on three domestic wheatsamples, and studied the effects of wheat indicators. To arrive tempering technology’s effecton moisture, ash and pasting properties and other physical and chemical indicators of wheatand flour, as well as the change of total number of bacterial colony, Escherichia coli number,the number of mold and yeast and bacillus cereus of wheat surface, and explore differenttempering technologyeffect on wheat quality and hygienic index. The main conclusions wereshown as follows:With the tempering time increasing,the total number of bacterial colonyand Escherichiacoli number of three wheat samples increased. With the increase of moisture content, the totalnumber of bacterial colonyand Escherichia coli number of three wheat samples increased, andthe number of mold and yeast increased slightly, and the bacillus cereus decreased. With thetempering temperature increasing, the total number of bacterial colony of three wheat samplesincreased, Escherichia coli numberand the number of mold and yeast increased first thendecreased.With the tempering time increasing, three wheat sample’smoisture and land values hadincreased first then decreased, and decreased attenuation values first decrease then increaseand last reduced,pasting temperature first increased and then decreased. With the increase ofmoisture content, three wheat sample’smoisture increased, crude protein content decreased,gluten index, gluten content and falling values were increased. Peak viscosity and setbackincreased.With the tempering temperature increasing, three wheat sample’smoisture increasedfirst then decreased, ash and gluten index were rising, also crude protein content and wetgluten has decreased to some extent. Peak viscosity, low viscosity and final viscosity upwardoverall and pasting temperature decreased first and then increased.Under vacuum tempering technology, with increasing tempering time, the total numberof bacterial colony of three wheat samples increased and then increased, and Escherichia colinumber increased. When vacuum pressure was increased, the number of microorganismsdecreased overall.With increasing tempering time, wheat moisture, gluten index and falling number had acertain negative correlation, ash reduced, attenuation values rise and regenerative effect onpasting properties of wheat variety. When vacuum pressure was increased, three wheatsample’smoisturehad increased first then decreased, crude proteinhad increased, gluten content andfalling number had a slight rise. The Changes in degree of vacuum had greaterimpact of gelatinization of wheat curve.With the increase of concentration of the brine tempering, the number of microorganismsreduced gradually. With increasing brine tempering time, the number of microorganismsincreased.With the increase of concentration of the brine tempering,moisture decreased, ash, wetgluten and gluten index rose to varying degrees. Peak viscosity had downward trend. Pastingcurves of the three wheat flour had a larger difference. With increasing brine tempering time,three wheat sample’smoisture, ash, crude protein, wet gluten and wheat gluten index hadimproved to some extent, whiteness decline. Pasting attenuation values showed an increaseafter the first decrease.Three tempering method comparison results: brine tempering and vacuum temperinginstinctively reach the water distribution under conventional tempering, the vacuumconditions ash will be under than conventional tempering and brine tempering. Particle sizedistribution of the three tempering method were not very different. The number ofmicroorganisms under vacuum tempering conditions was least.