Study On Changing Regularity Of Lipid During Controlled Atmosphere Storage Of Soybean

In our country, the quantity of soybean importing is as much as80%. It is about more than5500thousand tones. However, the logistics and the quality control technology are extremely crude, which cause serious damage. Especially the influence to the quality of the soybean oil is serious.Temperature, humidity, atmosphere and microorganism are the four main factors of soybean storage. Researches of appropriate proportion of storage atmosphere have become the hot point in recent years among the four factors. In this study, experimental materials were the soybean which has been harvested in Tianjin in2010and the one came from Uruguay. Water content, free fatty acid, germination percentage, protein content, grease extraction yield, peroxide value of soybean oil, and so on, under controlled atmosphere storage and vacuum storage were investigated. At the same time, the changes of qualities of soybean and soybean oil under storage in different granary were studied. The research contents of the study are as follows:1. During the controlled atmosphere storage, the texture of soybean full of Nitrogen at10℃is the best one. The germination percentage and linoleic acid content of soybean decreased a little, and the oil quality remains well. The second best one is the soybean with1%O2and20%CO2, and the next ones are the soybean with1%O2and5%CO2, and10%O2and20%CO2. The last one is the soybean with10%O2and5%CO2. Controlled atmosphere storage is better than conventional storage. It reveals that the quality metamorphism of soybean and oil will be restrained from less oxygen.2. Soybean stored in vacuum at different temperature showed that the changing of water content is not significant. The germination percentage and grease extraction yield are decreased while the temperature is rising. At the same time, peroxide value and acid value are rising. It reveals that the lower the temperature is, the better the quality of soybean is, and storing in vacuum at10℃is better than the others3. After rebuilding and the technology of energy-saving, the temperature in summer of granary is10.33℃lower than before. During the storage of180days, the germination percentage of soybean in reconstructed granary increased22.06%while the grease extraction yield increased4.30%. The peroxide value is.18.31%lower than control treatment, while the acid value is11.88%lower than it. Consequently, the quality of soybean oil is superior owing to granary rebuilding.