不同碾磨程度对糙米品质及相关性变化

The Effect of Different Degrees Milling on the Quality of Brown Rice and Their Correlation

摘要:

为了分析不同碾磨程度对糙米外观变化、营养物质含量、蒸煮及食味品质的影响，本文以空育131稻谷品种为原料进行研究，并采用斯皮尔曼方法分析碾磨程度与糙米品质之间的相关性，以获得口感与营养平衡的糙米。结果表明随着碾磨程度的增加（碾减率0%~7%，%均为质量分数），整糙米率下降1.20%，留皮度下降72.70%。营养组分含量呈显著下降，碾减率增加到7%时，蛋白质含量降低8.60%，粗纤维含量降低3.40%，淀粉含量升高11.00%，直链淀粉含量升高4.60%。Ca、Zn、Fe、Mn和Cu含量分别降低37.70%、19.21%、17.01%、37.52%、28.25%；VB1、VB2、VB3、VB5和VB6含量分别降低52.39%、25.00%、47.98%、35.36%、42.64%。蒸煮品质结果得出，碾减率从0%增加到7%时，吸水率、膨胀率、固形物损失率含量分别增加了50.88%、62.19%和5.27%。在碾减率4%时，崩解值最大（1232.56 Pa·s），糊化温度最低（85.73 ℃），此时口感最佳。通过相关性分析得出影响糙米品质好坏程度的指标从大到小的排列顺序是：粗纤维>最终黏度>热焓值>VB3>Ca含量>硬度。综上，得出结论：糙米在碾减率4%、留皮度88.80%时的碾磨程度比较好，此时口感比相同品种的市售糙米更好，营养更均衡。

Abstract:

In order to analyse the effects of different degrees of milling on the appearance changes, nutrient content, cooking and taste quality of brown rice, this paper was carried out with the kongyu 131 rice variety and the correlation between the degree of milling and brown rice quality was analysed using Spearman's method in order to obtain brown rice with balanced taste and nutrition. The results showed that as the degree of milling increased (milling reduction rate 0% to 7%, % are mass fraction), the whole brown rice percentage decreased by 1.20%, and skin retention decreased by 72.70%. The content of nutritional components showed a significant decrease, and when the milling rate increased to 7%, the protein content decreased by 8.60%, crude fibre content decreased by 3.40%, starch content increased by 11.00%, and straight-chain starch content increased by 4.60%.The content of Ca, Zn, Fe, Mn, and Cu decreased by 37.70%, 19.21%, 17.01%, 37.52%, and 28.25%, respectively; VB1, VB2, VB3, VB5 and VB6 contents were reduced by 52.39%, 25.00%, 47.98%, 35.36%, 42.64% respectively. Cooking quality results yielded an increase in water absorption, swelling, and solids loss content by 50.88, 62.19, and 5.27 per cent when the milling reduction rate was increased from 0 to 7 per cent, respectively. The maximum disintegration value (1232.56 Pa·s) and the lowest pasting temperature (85.73 ℃) were found at 4% milling reduction rate, when the taste was the best. The correlation analysis showed that the indexes affecting the degree of goodness of brown rice quality were, in descending order: crude fibre > final viscosity > enthalpy > VB3 > Ca content > hardness. In summary, it was concluded that the degree of milling of brown rice was better when the milling reduction rate was 4% and the degree of skin retention was 88.80%, at which time the taste was better than that of commercially available brown rice of the same variety and the nutrition was more balanced.