充氮气调储藏对普通晚粳大米品质的影响

Effect of Nitrogen Controlled Atmosphere Storage on the Quality of Ordinary Late Japonica Rice

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。

Nitrogen controlled atmosphere has been internationally recognized as a green grain storage technology.In this study,Jiangsu ordinary late japonica rice was used as a test material,and the effects of different nitrogen concentrations(88%,93%,98%)and different storage temperatures(10℃,20℃,30℃)on grain quality indexes during nitrogen controlled atmosphere storage were investigated.The results showed that the moisture 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(conventional storage).High concentrations of nitrogen controlled atmosphere treatments(93%and 98%)could effectively slow down the increase of fatty acid value,malondialdehyde content and electrical conductivity of rice,and could also significantly inhibit the rapid increase of final viscosity and water absorption of rice starch,while the changes of peak viscosity and attenuation value of rice were not significantly different from those of the control group.Meanwhile,the impact of 98%nitrogen controlled atmosphere storage on moisture content,fatty acid value,malondialdehyde 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 malondialdehyde content,changed most gently at 10℃.In conclusion,the combined treatment of nitrogen controlled atmosphere storage(98%)and low temperature(10℃)could effectively delay the quality deterioration of ordinary late japonica rice.