Effect Of Controlled Atmospehere With N₂on Rapeseed Quality

Rapeseed was an important economic crop, which was planted many area in china. Theannual output of rapeseed increased year by year.Rapeseed was an important raw material ofedible vegetable oil. Rapeseed storage was the key link between rapeseed production andprocessing, which played an important strategic significance to guarantee the safety of thecountry cooking oil. However, there was lack of systematical study on rapeseed in long term.Controlled atmosphere with filling nitrogen was a green environmental protection storagetechnology. The objective of this paper were to determine the variation rules of the quality ofrapeseed and the influence of storage conditions on the quality and provide theoreticalreference for the application of Controlled atmosphere with filling nitrogen in rapeseed.The rapeseed seeds with6.8%,8.3%,and9.8%moisture content were stored in storagefacilities with atmosphere controlled with98%N2（CA）and in storage facility withoutatmosphere controlled（NCA）at temperature of20,25℃,30℃,and35℃. The rapeseed seedswith6.8%,8.3%,and9.8%moisture content were stored in storage facilities with atmospherecontrolled with98%N2and in storage facility without atmosphere controlled at temperature of20℃,25℃,30℃,and35℃. During120days storing period, the storage quality, thephysiological quality, and the processing quality of the samples were determined every30days. The storage quality contented the rapeseed color, the color of oil extracted from thesamples, fatty acid value, peroxide value, fennel amine value of oil extracted from therapeseed. The physiological quality contented conductivity, germination rate, the activity ofcatalase,the protein content. The processing quality contented the oil content, fatty acidcomposition and iodine value.The results of the experience showed that there were obviously changes in the storagequality and physiological quality during storage of rapeseed while little changes in theprocessing quality. The data of the conductivity, germination rate, the activity of catalase,fatty acid value, and peroxide value were analyzed by using the regression treatment andvariance analysis methods. the results showed that: the germination rate and the activity ofcatalase gradually decreased, while the conductivity, the fatty acid value, and the peroxidevalue gradually increased as the storage time prolonged. the rapeseed moisture content, thestorage temperature and the storage time had remarkable effects on the conductivity, the fattyacid value, and the peroxide. there were significant difference between the rapeseed quality attemperature35℃and the rapeseed quality at temperature20℃,25℃,30℃. There were significant difference between the rapeseed quality of9.8%moisture content and the rapeseedquality of6.8%,8.3%moisture content. It was analyzed that the difference between thequality of rapeseed using CA method and that of rapeseed using NCA method. there weresignificant difference when the temperature was high or the rapeseed moisture content washigh.CA have the ability to postpone the effects of high temperature and high moisturecontent. It was necessary to do thing to control the rapeseed moisture content under9%beforestoring the rapeseed. In the storage period, atmosphere controlled with98%N2combining thetechnology of controlling the temperature under20℃will be better to maintain the storageand physical quality of rapeseed.