Analysis Of The Influence Of Different Milling Degrees On Rice Quality During The Storage Of Rice

China is the primary rice production country in the world, according to the statistic, Chinese rice production was 2.09 tons in 2015, and most of them need to be regularly stored, then will be processed into edible rice. For achieving reasonable processing accuracy and the best rice storage method, the paper has studied the variation of rice eating quality in different storage methods under different milling degree, which provides a theoretical basis and data support for Chinese rice storage and processing research.The paper treat the new harvest Suijing No.4, Chaobei No.2, Longjing No.40, Huixiang No.1and Daohuaxiang No.2, which is produced in Suihua and Wuchang area of Heilongjiang province as raw material, then the shell brown rice is milled for the first time, and put samples for 10 months storage. Six kinds of storage methods are listed as follows : conventional storage at room temperature, filling 100% CO2 gas storage at room temperature, filling CO2:N2=1:1 gas storage, low temperature of four degree, conventional storage at low temperature of 4 degree100% CO2 gas storage and low temperature of 4 degree filling CO2:N2=1:1 gas storage. The sampling period is one months, and the samples are five times of milling, then the paper analyzes each milled samples nutritional quality, cooking quality, texture characteristics and the variation of eating quality.By using FOSS near infrared grain quality detection analyzer, we analyze nutritional quality variation of the physical and chemical indicators in rice of storage under different grinding times for testing the distribution of nutrients in rice detection. The results show that with the increasing of the milling times, this method gradually reduces the moisture, crude fat,protein, ash and mineral content, but starch content gradually increases. During the storage of rice moisture was changed by the storage environment without regularity; Protein content decreases but don’t change significantly, under the conditions of low temperature charged of100% CO2 only once and twice milling rice protein decrease, 3-6 times milled rice protein has no obvious change; The changed trend of different milling times rice amyl have significant difference. The method of low temperature charged of 100% CO2 storage can effectively slow down the deterioration of nutritional quality, the nutrition quality of rice in storage of 3 milling is the best.By using RVA rapid viscosity analyzer and DSC differential scanning calorimeter to study in different storage methods under the storage of different grinding times we get rice cooking quality, RVA profiles, and do correlation analysis between rice physicochemical properties and pasting properties of cooking. The results show that rate of water absorption andexpansion increased as the increase of rice milling numbers, rice pH value and the dissolution of solid material decrease, rate of water absorption and expansion in 3 times milling is the minimum. The pH value of rice and solid dissolution are higher. Change in the RVA characteristic parameters shows that after storage different milling peak viscosity number of rice and breakdown values increases in the early stage of storage, and decreases with the extension of storage time.; setback decreases firstly and then increases; before 8 months of storage gelatinization temperature increases significantly. Obtained from the DSC curve of rice, rice enthalpy(ΔH) increased, storage condition and milling times had influence on the enthalpy value significantly(P < 0.05). The results of correlation analysis showed that the physicochemical indexes have significant correlation with cooking quality and starch pasting properties. On low temperature charged of 100% CO2 storage conditions under different milling times rice cooking quality, RVA profile and enthalpy value change relatively steady, in which three milling rice cooking gelatinization quality are better. No significant difference was found between the five kinds of rice.By using hardness tester and steamed rice taste meter to test rice texture quality and eating quality under the storage of different grinding times. The results show that with the extension of storage time, the rice taste value decreases, fatty acid value and steamed rice hardness gradually increases, the rice freshness FD value, steamed rice viscosity, elasticity reduces gradually. The correlation analysis shows that the physicochemical indexes, texture index has significant correlation with rice taste value. Storage conditions and processing precision of rice texture quality after storage have significant influence on taste value. Low temperature charged of storage 100% CO2 can delay the change of rice quality in a certain extent,the reservoir 3, 4 milling rice texture quality and eating quality are good. No significant difference are found between the five types of rice.