不同干燥方式下稻谷容重与含水量关系的研究

稻谷容重能反映稻谷籽粒的大小、形状、整齐度、胚乳质地等品质性状,与含水量等指标也密切相关。采用6个正常成熟收获的籼稻品种,研究不同干燥方式下,稻谷容重与含水量的关系。结果表明:(1)相同干燥方式下,稻谷容重因品种不同而不同,含水量为14.5%时,供试品种LP5容重最大,为552.8 g/L,LP7容重最小,为534.2 g/L。(2)相同品种的稻谷容重因干燥方法不同而不同,采用自然晾晒方式,当含水量在23%~17.5%时,容重缓慢降低;含水量在17.5%~10.5%时,容重升高较快;此后容重随着含水量降低极缓慢升高。采用45~50℃烘箱间歇式烘干降水时,当含水量在23%~14.5%时,容重随含水量的下降而降低;当含水量继续下降至9%时,容重值基本趋于平稳;此后,容重随含水量降低略有增加。(3)在稻谷安全贮藏水分范围(含水量14.5%),相同品种,自然晾晒降水的容重比烘干干燥的容重略高。(4)当稻谷含水量10.5%时,稻谷容重与含水率呈直线相关。初始容重值相近的品种,可共用回归方程,而初始容重相差较大的品种,回归方程不同。

Relationship Between Rice Grain Test Weight and Moisture Content under D ifferent D rying Methods

To assess the relationship between rice grain test weight and moisture content under different drying methods, six indica hybrid rice varieties were analyzed for test weight and moisture content. The results showed that rice grain test weight was closely related to moisture content in grain. Rice grain test weight varied with varieties. The highest was the va-riety of LP5 with the rice grain test weight 552.8 g/L and the lowest was the variety of LP7 with the rice grain test weight 534.2 g/L when the rice grain with moisture content of 1 4.5%within the same drying method. The rice grain test weight of the same variety was different because of different drying method. The rice grain test weight fell slowly when the rice grain with moisture content from 23% to 1 7.5% and increased quickly when the rice grain with moisture content from 1 7.5% to 1 0.5%and then rose slowly very much with moisture content reduced by natural air drying. The rice grain test weight fell down with moisture content fell down when it dropped from 23%to 1 4.5%by intermittent oven drying with the temperature of 45 ~50℃. The rice grain test weight trended to steady when the moisture content went below 9%and then increased slowly with moisture content continue to fall. The rice grain was higher by using the method of natural drying than intermittent oven drying when the moisture content was ranged of safety storage moisture （moisture content ＆lt;1 4.5%）of the rice variety. There were linear correlation between rice grain test weight and moisture content when the moisture content was above 1 0.5%. The regression equation can be shared when the varieties with close initial test weight＆amp;nbsp;but the regression equation was different when the varieties with significant different initial test weight.