为了探讨糙米储藏品质指标的变化规律及有效控制糙米仓储流通过程中的品质变化,选择2个粳型糙米样品进行实验室模拟低温、常温及高温储藏,条件分别为15、25及35℃,相对湿度为75％,储期为210d,每30 d取样1次,测定储藏过程中发芽率、生活力及脂肪酸值3项生理生化指标变化趋势并做动力学分析.结果显示,随储藏时间的延长,样品的发芽率、生活力这2项指标均呈下降趋势,且储藏温度越高下降趋势越剧烈,脂肪酸值在各储藏条件下随着储藏时间的延长均呈上升趋势.对各指标进行动力学分析后显示,一级动力学模型可以很好反映这3项指标的变化,并且糙米储藏中脂肪酸值的增加、发芽率及生活力的衰减随绝对温度倒数的变化均符合Arrhenius方程.这3项指标在储藏过程中均属于需能反应(△G＞0),不同糙米品种相对应的活化能存在差异,辽星样品的3项指标反应活化均高于盐丰样品,且同一糙米品种的生活力与发芽率的活化能明显高于脂肪酸值.陈化动力学的运用可为仓储流通过程中糙米品质变化的预测和控制提供理论依据.%In order to investigate the quality changes of stored brown rice and control the quality changes during brown rice storage and circulating effectively, perpetrating simulating storage in laboratory with 2 kinds of round shaped brown rice, the storage conditions were 15℃、 25℃ and 35℃, relative humidity 75%, the germination rate, viability and fatty acid value were determinate every 30 d and lasted for 210 d. The results showed that germination rate and viability of brown rice increased with the storage time prolonging and the deterioration enhancing, while fatty acid value decreased. The kinetics analyzes results showed that these trends could be well reflected by first order kinetics, and all of these are suitable to Arrhenius equation. Different varieties of brown rice with different activation energy, which of Liaoxing was greater than that of Yanfeng at the three parameters, and the activation energy of germination rate and viability were greater than that of free fatty acid with one sample. The results could be useful to predict and control quality change during brown rice storage and distribution process.
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