碾磨度对粳稻外观品质和食味理化特性的影响

Effect of milling degree on the appearance quality and physicochemical properties to the palatability of japonica rice

以3个粳稻品种(系)为材料,设置5种碾磨处理,测定稻米外观和理化特性,研究碾磨度对粳稻外观品质和食味理化特性的影响。随着碾磨度的增加,米粒长度减小,碾磨度超过13%,长度显著下降(P<0.05),碾磨对短粗籽粒稻米的宽、厚及长宽比影响较小。碾磨度为9%~10%可以满足消费者对稻米白度的需求,当碾磨度超过9%~10%时,3个品种(系)碎米率增幅加大。随着碾磨度的增加,蛋白质含量和米饭硬度下降,直链淀粉含量、米饭黏度和食味值提高。从糙米到碾磨度15%,津原U99、津原45和晶香432蛋白质含量分别下降15.9%、14.6%和20.4%。碾磨度为2%时,米饭硬度分别下降49.6%、49.8%和46.5%,此后下降缓慢。碾磨度与米粒长度、蛋白质含量、米饭硬度和硬度/黏度呈极显著负相关(P<0.01),与稻米白度值、碎米率、直链淀粉含量、米饭黏度和食味值呈极显著正相关(P<0.01)。碾磨度对稻米食味理化特性的影响存在品种间差异。津原U99和津原45最适宜的碾磨度为9%,晶香432最适宜的碾磨度为13%,可以确保良好的食味理化特性并满足消费者对外观品质的需求。

Three japonica rice varieties(lines)were used for five different degrees of milling(DOM)treatment in order to determine the effect of milling on the appearance quality and physicochemical properties related to the palatability of japonica rice.The results showed that the increase in DOM resulted in the reduction of grain length and the length decreased significantly(P<0.05)when the DOM exceeded 13%.The effects of milling on the width,thickness and length/width ratio of short-bold grains were small.And when milling degree of 9%-10%could meet consumers′demand for rice whiteness and the broken rice rate of the three varieties(lines)increased when the milling degree exceeded 9%-10%.Moreover,the protein content and hardness of cooked rice decreased whereas the amylose content,the adhesion and the palatability value of cooked rice increased with an increase in DOM.From brown rice to 15%milling degree,the protein content of Jinyuan U99,Jinyuan 45 and Jingxiang 432 decreased by 15.9%,14.6%and 20.4%,respectively.Furthermore,when the milling degree was 2%,the hardness of cooked rice decreased by 49.6%,49.8%and 46.5%respectively,and after that,it fell slowly.DOM showed a significantly negative effect on grain length,protein content,hardness as well as hardness/adhesion of cooked rice(P<0.01),however,with an increase in DOM,whiteness value,broken rice rate,amylose content,adhesion and palatability value of cooked rice were significantly increased(P<0.01).DOM affected the physicochemical properties related to palatability,but existed varietal difference.It was suggested that the most suitable DOM for Jinyuan U99 and Jinyuan 45 was 9%,and for Jingxiang 432 it was 13%.Above treatment can ensure physicochemical properties related to palatability and meet consumers'needs for appearance quality.