粳稻谷储藏期间品质变化的动力学研究

通过对不同温度条件下(15℃、20℃、25℃、30℃)储藏的粳稻谷过氧化物酶(POD)活性、峰值粘度变化进行监测(储藏时间为180d,测定周期为30d),结合动力学分析方法,在研究储藏条件对粳稻谷品质影响的基础上建立相应的品质变化预测模型。结果表明:过氧化物酶活性随着储藏时间的延长而逐渐下降,且温度越高,下降得越快,在温度为30℃、25℃、20℃、15℃条件下储藏180d后,粳稻谷过氧化物酶残余活力依次下降至16.74%、23.85%、38.35%、40.17%;峰值粘度随着储藏时间的延长而呈现波动上升的趋势,温度越高,上升的趋势越明显,在30℃条件下储藏180d后,峰值粘度上升至3495cP,而在温度为25℃、20℃、15℃条件下储藏的粳稻谷样品,峰值粘度依次上升至3307cP、3262cP、3018cP。粳稻谷过氧化物酶活性、峰值粘度的预测模型依次是:lnAt=-e-31007.16/RT×t+4.6052、lnAt=-e-24467/RT×t+7.7337。动力学模型预测值与实际测量值的相对误差在1%~12%之间,可以对储藏期间粳稻谷品质变化进行预测。

DYNAMICS ANALYSIS OF QUALITY CHANGES DURING JAPONICA RICE STORAGE

Monitor the changes of peroxidase（POD） activity and peak viscosity during japonica rice storage（the storage time for the 180d, the measurement cycle for 30d） under different temperatures（15 ℃, 20℃, 25℃, 30℃）, binding kinetics analysis method to research the influence of storage conditions on the quality of the japonica and establish the dynamics model of quality changes. The results show that the peroxidase activity gradually decrease with the storage time, moreover, the higher the temperature is , the faster the decrea- sing is, after storage 180d under the temperature of 30℃, 25℃, 20 ℃, 15℃, The peroxidase（POD） activity of japonica in turn fell to 16.74%, 23.85%, 38.35%, 40.17%; the peak viscosity is on the increase with the storage time, the higher the temperature is, the more obvious the trend of the increasing is, after stor- age 180d under the conditions of 30℃, the peak viscosity increased to 3495cP, although at a temperature of 25℃, 20℃, 15℃ storage, the peak viscosity in turn is rising to 3307cP,3262cP,3018cP. The forecast model of POD： lnAt= -e-31007.16/RT× t＋4. 6052 ;The forecast model of peak viscosity： lnAt= --e-24462/RT× t＋7. 7337. The relative error of dynamics model of prediction value and actual measurement value is be- tween 1% and 12%, it shows that this model can better predict the quality changes during storage.