优质籼稻储藏品质控制指标的确定

摘要

研究优质籼稻在高大平房仓中常规储藏条件和准低温储藏条件下储藏品质的变化规律,探讨优质籼稻储藏品质与各项指标之间的关系,筛选出几个能反映储藏优质籼稻品质变化的敏感指标,最终确定优质籼稻储藏品质控制指标为米饭感官评分、脂肪酸值、黄粒米、色泽气味、米饭硬度和最终黏度.将米饭感官评分随储藏时间的变化进行曲线拟合,从而建立储藏期预测模型.对各项控制指标随储藏时间的变化进行曲线拟合,参照阈值确定方法“多数原则法”,得到保质储藏期和安全储藏期内优质籼稻储藏品质控制指标的限定范围:保质储藏期内要求:色泽气味正常、米饭感官评分≥70分、脂肪酸值≤23.1 mgKOH/100 g干基、黄粒米含量≤0.5％、米饭硬度≤3.6、最终黏度≤3 284 cP;安全储藏期内要求:色泽气味正常、米饭感官评分≥60分、脂肪酸值≤26.2mgKOH/100 g干基、黄粒米质量分数≤1.1％、米饭硬度≤3.8、最终黏度≤3 412 cP.%The research focused on quality variations of high quality indica rice stored in large warehouse under conventional storage and quasi low temperature storage.Relationship between physicochemical properties and storage quality of high quality indica rice was discussed;sensitive indexes of stored high quality indica rice were selected.Rice sensory evaluation,fatty acid value,yellow rice kernels,color and odor,rice hardness and final viscosity were finally decided as quality control indexes of stored high quality indica rice.A mathematical storage forecasting model was established between rice sensory evaluation and storage time.In addition,functional relation between storage time and each quality control index was established,and according to basic threshold determination rule-" majority principle",the limit shelf of quality control indicators of stored high quality indica rice in the shelf life and the safety period was determined:demands in the shelf life:color and odor is normal,rice sensory evaluation≥70 marks,fatty acid value≤23.1 mgKOH/100 g(dry basis),yellow rice kernels≤0.5％,rice hardness≤3.6,final viscosity ≤ 3284 cP;demands in the safety period:color and odor is normal,rice sensory evaluation ≥60 marks,fatty acid value ≤ 26.2 mgKOH/100 g (dry basis),yellow rice kernels ≤ 1.1％,rice hardness ≤ 3.8,final viscosity ≤ 3 412 cP.