Development,Ageing And Digestion Properties Of Yin Rice Rice Cakes

Rice is main crops food in south China. China’s total grain output was 546.41 million tons in 2010,31.32 million tons of which were rice, only 6% of total rice for processing accounts, which caused great losses. So to strengthen the basic research and application of deep processing of rice in research, development, improve the added value of rice has become the focus of attention. With the rapid development of biotechnology, through the microorganism fermentation to improve the functionality of rice products and the added value of products is an effective way. Yin rice cakes production process was improved, japonica rice and glutinous rice were mixed as raw material fermentated in 25℃ for 2 days, then produced by pulping, pressure filtration, sieving, cooking and extrusion molding process. Analysis for rice grain structure and molecular structure of different fermentation time Yin rice were studided, the optimum process conditions of Yin rice cakes were determined through the single factor experiment and correlation analysis. The basic physical, digestive properties, aging properties and chemical properties of rice cake were analyzed. The main research contents and results were as follows:1 Analysis for raw rice and Yin rice in different fermentation conditionsFirstly analyzing the basic nutrition materials of raw rice, including protein, crude fat, ash content, amylose, moisture content, etc. Rice granule properties and gel strength were studied using the laser particle sizer, dynamic rheometer (DMA), quality and structure (TA) analyzed on the original rice and different fermentation time (2-4 days) Yin rice. Results show that the soak rice gel strength maximum of 2 days; Soak 2 day Yin rice starch median diameter, volume average distance, area average distance maximum and the smaller specific surface area; DMA determination of rheological properties, the result shows that final viscosity, breakdown value, such as energy storage modulus and energy consumption modulus of different fermentation time Yin rice have different degree of change.2 The determination of process conditions of Yin rice cakesThrough single factor experiment and the weight score calculation to build evaluation system, of which, viscosity, hardness, chewiness, cohesion, elasticity and resilience as the main evaluation index, statistical method is applied to calculate the corresponding weight score of every index, TA is adopted to improve the single factor experiment process comprehensive rating of each parameter, to determine the final Yin rice cakes manufacturing process. The final result is:the raw glutinous rice, japonica rice quality ratio of 1:2; 2 d soaking time, suction filter 40 min after the wet vacuum,20 mesh shattered,7 min steamer steaming, knead extrusion, cooling stereotypes 6-8 h, vacuum packing.3 Compared of basic nutrition and digestive properties between Yin rice cake and traditional rice cakeFirstly determined by chemical method to compare basic nutrients in two kinds of the rice cake, results show that moisture content of Yin rice rice cake was significantly higher than that of conventional rice cakes, its water-holding capacity is obviously better than the traditional one, and at the same time, the relative contents of amylose of Yin rice rice cakes were decreased, amylopectin content increased; Using chroma meter on the comparison of colour of two kinds of rice cakes, whiteness (L value) of Yin rice rice cakes was also significantly higher than traditional rice cakes; each index of two kinds of rice cake shows significant difference. Astral imager (TA) on the comparison to two kinds of rice cakes, the score of Yin rice cake was higher than traditional cakes so did sensory evaluation, it can be seen in, viscosity, hardness, chewiness and flavor of the four indicators of Yin rice cakes were superior to traditional rice cakes. Using ultraviolet spectrophotometer test the soup turbidity of rice cakes at 720 nm, results show that soup turbidity of Yin rice is lower than the traditional rice cakes. Using electronic tongue determination of several kinds of rice cakes, results show that the taste of rice rice cakes, and other two traditional rice cake have significant differences, differences between traditional rice cake is smaller.4 Digest properties of Yin rice cakes and traditional cakesRice starch digestibility was measured by resistant starch and sugar index, in vitro digestion kinetics experiment was carried on the analysis, the results show that resistant starch content of Yin rice rice cake is lower than lab homemade cakes and traditional rice cakes (ningbo), respectively,8.13%,11.71%,10.92%, which were of significant differences; Three rice cakes came to hydrolysis equilibrium in the 60 min-90 min, hydrolysis rate increase slowly after 90 min, the hydrolysis rate of Yin rice cakes was higher than the other two; Yin rice cakes were easier to digest for higher glycemic response.5 The aging characteristics research of Yin rice cakes and traditional cakesUsing differential calorimeter scanner (DSC), X-ray diffraction (XRD), scanning electron microscope (SEM) and 1 H-NMR instrument is studied in different rice cakes for aging properties under different storage conditions. Results shows that the enthalpy change value of Yin rice cakes is less than the traditional cakes under the condition of 4 ℃ for one week and -18℃ storage for two weeks; Under the same conditions, the crystallinity and crystallinity change value of Yin rice cakes were less than the traditional rice cakes; After binarization SEM image calculation shows that structure of Yin rice cake after aging is also relatively more complete and dense than traditional rice cakes; the relaxation changes along with the changes of the aging time of rice cakes, T22 value of Yin rice cakes is lower than traditional rice cakes, T22 proton density were higher than that of traditional rice cakes. Yin rice cakes can delay the aging process compared with traditional cakes.6 Yin rice cake improverSelecting the appropriate thickeners (edible glue) and edible emulsifier and enzymes to research single factor experiment, orthogonal experiments were carried on according to the results of the single factor experiment and calculation. The results was that an optimal distribution formula (W/W, based on total raw material quality) as follows:xanthan gum 0.15%, and 0.045% of a-amylase,0.15% monoglycerides.