Effects Of Rice Bran Stabilization And Its Additive Level On Indica Rice Flour And Rice Cake

Rice bran is rich in dietary fiber and can be used as an ingredient to improve the nutritional quality of foods.Stabilization treatment can effectively delay the quality decline of rice bran during storage and prolong its shelf life.Rice cake is a traditional fermented rice product,which has a unique flavor,soft and elastic texture.The stabilized rice bran is added into rice flour to make rice cake,which can significantly improve the nutritional quality of rice flour and also change the taste quality of rice cake.It is a scientific dietary collocation.In this paper,the physical and chemical properties of rice bran treated by different stabilization methods were studied,and the effects of different rice bran addition levels on the properties of indica rice flour and the quality of rice cake were explored.Finally,the quality change mechanism of rice cake under the condition of precooling and refrigeration was preliminarily explored.The specific research was as follows:1.Explored Natural cooking(NC),High-pressure cooking(PC),Atmospheric steam(AS),Microwave processing,MP and Extrusion processing(EP)affect the physicochemical properties of rice bran(basic component,color,water holding capacity,oil holding capacity,water solubility index,swelling capacity and total free phenolic flavonol content).The results showed that the contents of crude protein,ash,color and total free phenol of rice bran samples increased significantly after stabilization,water holding capacity,oil holding capacity,water solubility index,swelling capacity and total flavonoids changed in different degrees,which indicated that the stabilization treatment could effectively regulate the physicochemical properties of rice bran samples.2.Recombinant Rice flour was prepared by mixing different stabilized rice bran with indica rice flour(RF)in different addition ratios(3%,6%,9%,12%,15%).The silty properties(expansion potential,solubility,nutritive properties,thermodynamic properties,gelatinization properties,rheological properties)and gel properties(rheological properties,freeze-thaw stability)of recombinant rice flour were studied.The results showed that the addition of rice bran increased the solubility(except PC-3%)and decreased the swelling potential significantly.The viscosity of the reconstituted paste is reduced,the stability is enhanced,the gelation is enhanced,and more solid properties are displayed.The elasticity and viscosity of the recombinant powder gel system were enhanced,the fluidity was weakened,and the water extraction rate was decreased,it was particularly significant at 9%rice bran content,which indicated that adding stabilized rice bran could effectively regulate the gel properties of rice starch based foods.3.Studied the application of reconstituted rice flour in rice cake,and explored the feasibility of applying reconstituted rice flour in rice cake products by measuring the specific volume,texture characteristics,texture characteristics and sensory evaluation of rice cake.The experimental results showed that the addition of rice bran significantly increased the specific volume(except PC-3%),the number of pores,the brightness,wall thickness,pore diameter,the ratio of coarse to fine pores,and the hardness,viscosity,chewability and adhesiveness of rice cake.The texture quality of rice cake with 9%rice bran content was the best,which could be accepted by consumers.The addition of rice bran(9%or less)can improve the quality of rice cake.4.The changes of water distribution and coagulation enthalpy of rice cake with 9%rice bran content were investigated during freezing storage(-20℃)at different precooling temperatures(-20℃,-40 ℃,-80℃).Through experiments,it is found that stabilized rice bran and lower precooling temperature can strengthen the distribution of water more effectively,and weak bound water will transfer to strong bound water and free water.With the increase of storage time,the proportion of three kinds of water in brown rice cake fluctuated.Stabilized rice bran and lower precooling temperature(-40℃,-80℃)can also achieve lower enthalpy value of coagulation.The enthalpy of coagulation of rice cake with 9%rice bran content was significantly lower than that of white rice cake group.