大米安全储藏包装方式与堆垛方法的设计

大米的包装方式与堆垛方法在一定程度上会影响大米在储藏期间的品质变化,良好的包装方式与正确的堆垛方法可有效防止大米陈化、霉变,延缓其营养品质下降。本文分析了包装材料、包装方式和堆垛方法等因素对大米安全储藏的影响,介绍了可装乘净含量25kg大米的双层真空包装和可装乘净含量50kg大米普通包装的设计,并设计了针对2种包装方式的吨袋堆垛、散袋堆垛及滑托板堆垛方法,这些设计方案不仅可以减少大米的储藏损失,而且提高了仓库的利用率,同时也有利于对仓储进行科学管理。

基于近红外光谱检测技术的稻米溯源研究进展

稻米的品质受产地的气候和土壤条件、种植方式、品种、加工等多因素的影响。近年来,近红外光谱(near-infrared spectroscopy,NIRS)在农产品检测分析领域得到了广泛应用。本文针对近年来NIRS技术在稻米的营养成分、产地及品种溯源、及加工溯源分析等方面的应用进行分析总结,阐述了NIRS技术在稻米检测中的应用现状,以期在我国稻米品质控制中NIRS技术推广得到更好的应用。

充氮气调储藏对普通晚粳大米品质的影响

充氮气调是国际公认的绿色储粮技术。以江苏普通晚粳大米为试材,研究其在不同氮气浓度(88%、93%、98%)气调处理和不同储藏温度(10、20、30℃)下大米品质指标的变化规律。结果表明:在20℃条件下,不同浓度充氮气调组大米的水分含量均在12.85%~13.15%间波动,显著低于常规储藏组;高浓度充氮气调处理(93%和98%)对大米的脂肪酸值、丙二醛含量、电导率的变化有显著减缓作用,也能明显抑制大米淀粉最终粘度和吸水率的快速增加,而大米峰值粘度和衰减值的变化与常规储藏组无显著差异。同时,探究了在10、20、30℃条件下,98%氮气浓度气调储藏对大米水分含量、脂肪酸值、丙二醛含量、电导率、糊化特性、吸水率的影响,结果发现除丙二醛含量外,其余指标在10℃时变化最平缓。综合来看,充氮气调(98%)和低温(10℃)协同处理能较好地延缓普通晚粳大米的品质劣变。

Effects of Nitrogen-controlled Atmosphere Storage on the Quality of Ordinary Late Japonica Rice

Nitrogen-controlled atmosphere has been internationally recognized as a green grain storage technology.This study used Jiangsu ordinary late japonica rice as the test material and investigated the effects of different nitrogen concentrations(88%,93%,and 98%)and different storage temperatures(10,20,and 30℃)on the rice quality indexes during nitrogen-controlled atmosphere storage.The results showed that the water content of rice in different nitrogen-controlled atmosphere groups fluctuated between 12.85%~13.15%at 20℃,which was significantly lower than that in the control group.High-concentration nitrogen-controlled atmosphere treatment(93%and 98%)effectively slowed down the fatty acid value,malondialdehyde(MDA)content,and electrical conductivity of rice,and also significantly inhibited the rapid increase in the final viscosity and water absorption of rice starch,while the changes in the peak viscosity and attenuation value of rice were not significantly different from those of the control group.Meanwhile,the impacts of controlled atmosphere storage with 98%nitrogen concentration on the water content,fatty acid value,MDA content,electrical conductivity,gelatinization characteristics,and water absorption of rice at 10,20,and 30℃were studied.It was found that all quality parameters,except the MDA content,changed most gently at 10℃.In conclusion,the combined treatment of nitrogen-controlled atmosphere storage(98%)and low temperature(10℃)can effectively delay the quality deterioration of ordinary late japonica rice.

真空包装粳米启封后品质变化的研究

为探讨真空包装启封后对大米品质的影响,以普通晚粳和南粳46大米为对象,将其储存在室温和30℃、70%相对湿度条件下,对启封储存期间粳米水分、色泽、脂肪酸值、丙二醛(Malondialdehyde,MDA)、蒸煮特性和质构特性进行研究。结果表明,真空包装启封后的粳米在不同温度储藏期间,各品质特性均发生显著变化,且随着温度的升高,变化幅度越大。其中,普通晚粳大米水分、b值、脂肪酸值、吸水率和膨胀率增加幅度及米汤干物质下降幅度均大于南粳46大米,而南粳46大米在L值和a值上的下降幅度和MDA含量的增加幅度比普通晚粳大米的变化更显著。随着启封储藏时间延长,普通晚粳和南粳46大米的硬度先下降后上升,黏性的变化趋势与之相反;咀嚼性和胶着性随着启封储藏时间变化很大,下降幅度大于弹性。主成分分析显示,储藏时间和高温高湿对粳米品质劣变影响显著。该结果为真空包装启封后粳米品质变化的控制研究提供了一定指导。