Effect Of Whey Protein Cold Gel On Quality Of Rice Bread

In recent years,the research of gluten-free products has been an emerging research topic,because it can be a good resolution to patients with celiac disease(CD).Rice flour is considered highly suitable for preparing GF products because it is bland and colorless,easily digested,and hypoallergenic.This research mainly focused on the influence of whey protein cold gel on characteristics of rice dough and the baking properties of rice bread,and then the formula was optimized.The rheological properties,average particle size and gel texture properties of whey protein cold gel were investigated by dynamic rheometer and Texture analyzer(TA)respectively.Whey protein cold gel were prepared at different concentrations(8%-12% w/w).The results showed that gel prepared with10% whey protein possessed a stronger structure and apparent viscosity than that of other concentrations.Average particle size nearly reach to 3264 nm when the concentration of cold gel were10%,with a best gel texture,flexibility and cohesiveness.The rheological properties,proofing conditions and thermodynamic properties of dough with different concentrations of whey protein cold gel were measured by dynamic rheometer and differential scanning calorimetry(DSC).The results showed that the G ’and G values and the volume of dough were the largest,when the concentration of whey protein cold gel was 10%.Moreover,compared with the control,all doughs with protein cold gel possessed a bigger volume during fermentation.The paste enthalpy of dough was decreased with addition of protein.The texture characteristics,microstructure and aging characteristics of the bread were measured by bread volumetric analyzer,TA,scanning electron microscopy(SEM)and so on.The results showed that bread containing whey protein cold gel showed improved the specific volume and texture characteristics.Bread with addition of 10% whey protein cold gel showed improved texture properties,including elasticity,cohesion and recovery.The hardness and cohesiveness of bread were reduced.Results from microstructure of bread cells were more uniform and numbers of bubbles were increasing.Results from sensory evaluation showed that bread with 10% protein possessed the best sensory quality including the color,flavor and taste.And also,the volume was significantly increased,the air distributed evenly,the sensibility score reached to 7.43,the rate of staling was slowed down during storage.The results showed an optimized formulation with SMP8%,HPMC 3%,and DATEM 0.5%.Compared with the rice control,the optimals exhibited a better specific volume,texture characteristics,and sensory score reached to 7.92,the staling rate of bread was slowed during storage.The rate of water reduction was reduced by 15% and amylopectin retrogadation enthalpy deceased by nearly 21%.