Studies On Controlled Atmosphere Storage And Changes Of Lipids Of Rice

Temperature, humidity, atomsphere and microbials are the four main factors of rice storage. Research of appropriate propotion of storage atomsphere became the hot point in recent years among the four factors. In this study, the physiological and biochemical properties of Tianjin2007rice, including water content, free fatty acid, total aciddity, peroxide volume, linoleic content, lipase activity, under controlled atomsphere storage, modified atomsphere storage and vacuumn storage were investugated. However, the effect of lipids change on rice under modified atomsphere storage were studied especially. Moreover, the effects of ZnO films on coliforms, metaphilic bacteria and mold/yeast in paddy, brown and white rice were evaluated at20℃in the air. All the results of study are as follows:1. During the controlled atomsphere storage, the texture of rice at10℃,20%CO2maitained best than other teatments and took on well cooking quality, no chalky phenomenon, the best cooking taste and viscosity, reliability, integrity, lower increase in free fatty acid and total aciddity.2. Paddy in enclousure under modified atomsphere storage showed better results than modified atomsphere packaging storage at20℃. Stable and rapid formation of a high CO2environment in enclousure delayed the aging of rice earlier, and the treatment of paddy showed lower loss of linoleic content, lower lipase activity, lower increase in free fatty acid, total aciddity, preoxide content than modified atomsphere packaging storage, it is indicated that high CO2may inhibited the change of lipids in paddy.3. Rice stored in vacuumn at different temperatrue showed that the changing range of water content, free fatty acid, total aciddity is not sinificant. Rice had a concentrated flavor, good cooking quality, no caking phenomenon. Rice stored at10℃in vacuumn showed a little better quality than that of at30℃, the effect of temperatrue on rice during vacuumn storge is not sinificant.4. The antibacterial effect of ZnO films on coliforms in paddy, brown and white rice is sinificant, however, it is not so significant on metaphilic bacteria in paddy, brown and white rice, but inhibited the growth tendecy of metaphilic bacteria.During the whole storage time, there is no antibacterial effect of o ZnO films mold/yeast in paddy, brown and white rice.