Rheological Property Of Rice Dough

With the development of food industry,food rheological research become more and more widely.The rheological properties of starch and starch paste were studied very hot.The purpose of this study is to make early indica rice as the research object,and to explore the relationship between rice molecular structure,physical and chemical properties and its rheological properties;the rheological properties of rice flour by natural fermentation;the rheological properties of rice with edible glue.The arm of this study was to do some work for the future research about the rheological properties of rice starch.The main research contents were as follows:(1)The rheological properties of 16 kinds of rice in different thermal processes were studied by dynamic rheological analyzer.Results indicated that the total starch content significantly increased the peak temperature of the storage modulus,but the protein content promoted a significant decrease in the peak of tan?.Rice starch reduced significantly than rice flour in the gel strength,gelation speed,G'max and G"max,indicating that the proteins could be effectively strengthen and promote the formation of gel network,increase the hardness and strength of the starch paste.The smaller the particle size of rice flour could gelate quickly and its gel was stronger.The freeze-dried rice flour particles were easier to water swelling and amylose precipitated faster,then forming a stronger gel network.(2)The pasting and textural property parameters of rice flour,rice starch and natural fermentation flour were compared by using rapid visco analyser(RVA)and textural analyzer;and their gelation and retrogradation were investigated by dynamic rheometer.The results showed that:gelation speed,gel strength and gelatinization temperature of the rice starch was the lowest.The peak viscosity,breakdown,final viscosity,setback of the rice starch was the highest.The rice starch had the higher than the rice flour in elasticity and viscosity of the starch gel,but its hardness was the lowest.Protein content,gel strength and gelation speed of the rice flour were significantly reduced by the natural fermentation,while peak viscosity,breakdown,final viscosity,setback was significantly increased.The total starch content and amylose content did not change significantly.With the moderate degradation of rice starch molecules,the macromolecules of the molecular content would be relatively decreased and the medium molecular weight would be relatively increased.The starch released from the combination with protein,forming a uniform and dense gel and giving the natural fermentation flour good textural properties.(3)The effect of the addition of different proportions of carrageenan,xanthan gum,sodium alginate on the viscosimetric and rheological properties of the rice flour dough were evaluated.The results showed that:the addition of 0.4%carrageenan significantly increased the gel strength of rice flour;the addition of 0.8%xanthan gum significantly reduced the gel strength of rice flour,while in the flexibility of rice flour promoted a significant decrease;the addition of the alginate significantly inhibited the formation gel of the rice flour.Carrageenan and xanthan gum as edible gum can be used to improve the texture of rice gel products.