Study On Effect Of Microwave Preservation Of Rice

In this paper,we mainly studied the effect of microwave treatment on the quality of rice and the pests in rice,and optimized the optimal parameters of microwave combination of rice.At the same time,the preservation effect of microwave preservation and controlled atmosphere preservation was studied.The main contents and conclusions are as follows:(1)Microwave power,the processing time and the moisture content in rice were used to study the effects of different microwave treatments on the water content,taste value,fatty acid value,total number of surface fungi,volatile sexual material,internal microstructure and other quality.The results showed that the moisture content of rice was almost unchanged after microwave treatment,A certain range of microwave parameters could increase the taste value of rice.With the increase of microwave power or time,the fatty acid value is gradually reduced,and the microwave treatment can achieve the desired bactericidal effect.The total number of molds on rice is obviously less.The microwave power and microwave treatment time had a significant effect on the fatty acid value and the number of moids(p<0.01).The water content of rice had a significant effect on the fatty acid value and the number of molds(0.01<p<0.05).The microwave conditions used in the experiment had little effect on the volatile matter of rice.After the microwave treatment,the endosperm cells of the rice cross section were fused and the radial contours became blurred.With the increase of the microwave treatment conditions,the granules of the complex were disintegrated and the small starch granules increased.(2)Three-factor four-level orthogonal experiment design was used to optimize the optimal microwave parameter combination of microwave on rice,the taste value,fatty acid value,the number of rice surface mold,rice texture,characteristics of gelatinization as examining index,the members hip-degree method was used to comprehensively evaluate the quality of rice.The results showed that the order of the three factors on the significance of rice comprehensive score was as follows:microwave time>moisture content>microwave power.The best microwave preservation parameters were as follows:rice water content 15.5%,microwave power 640 w,microwave time 60 s.The parameters were tested with repeatability stability test.It was found that the process parameters were highly reproducible,and the membership score of microwave rice was the highest,which was 0.916.(3)Pests eggs,larvae,pupae and adults which contained in rice were treated with microwave respectively.The results were found that the same microwave treatment time,the greater the power the higher the mortality rate,the same microwave power,processing time to extend the mortality rate increased.In the same microwave treatment,the sensitivity of different insect pests to microwave sensitivity was different.The order of susceptibility of moth-eating pests to microwave was as follows:pupae>adults>larvae>eggs,the order of susceptibility of powder pests to microwave:Larvae>adult>pupa>eggs.Microwave power,treatment time and the interaction of two factors have a significant effect on the mortality of each insect species.The results showed that the parameters of 640 W,60 s and 800 W,50 s were 100%lethal to the stored grain pests,and the microwave conditions of 640 W and 60 s were optimaled,as under the condition,rice quality better.(4)the microwave preservation technology and atmosphere preservation technology combined with rice storage preservation,compare the preservation effect of different preservation methods.The results showed that rice with prolonged storage time,the taste value,the water content and the activity of lipase were decreased,the fatty acid value,the color difference became and the hardness of rice became larger.Rice quality overall presentation:microwave treatment + gas drum + deoxidizer group>microwave treatment + deoxidizer group>microwave plastic group>gas drum + deoxidizer group>deoxidizer plastic group>no treatment plastic group.The results showed that the combination of different preservation methods could reduce the rate of rice quality reduction,and it was better to preserve the quality of rice than single preservation.With multiple indexes of rice and eating value regression analysis,each kind of fresh preservation to get a mathematical model which were verified.The results showed that the models are reliable and can be applied to the evaluation of rice quality with multiple indexes.