粳米对糯米糊化特性的影响研究

Effects of japonica rice on the gelatinization properties of glutinous rice

在总重为20g的情况下于糯米中掺入粳米，使糯米中分别含有0％、5％、10％、15％及20％的粳米，充分混合后粉碎并过筛，取筛下物进行糊化特性测试。本文研究了四种糯米中掺入不同比例的粳米后对其糊化特性中各个参数的影响，实验结果表明，由于粳米的混入，增加了糯米的回生性能，并且衰减值表现出下降的趋势。通常，糯米中直链淀粉含量在0％～2％，其含量的检测比较繁琐，另外，当糯米中掺有粳米的比例在5％或10％时其直链淀粉的含量仍低于2％时则无法由直链淀粉的含量来判定其是否掺有粳米。本文通过糯米中混入不同比例粳米后糊化特性的改变，提出了回生值／衰减值（称为粳米影响因子）用来定性鉴别糯米中是否掺有粳米的一种补充手段，弥补了以直链淀粉含量高低来评判糯米中是否掺有粳米的方法不足性。

In total weight of 20g, the japonica rice was mixed with glutinous rice at the ratio of 0%, 5%, 10%, 15% and 20% respectively. Then the mixture was crushed and sieved before the test. In this paper, the effects of different proportion of japonica rice on the pasting properties of glutinous rice were studied. The results showed that the retrogradation properties of the mixed rice increased and degradation value decreased. Normally, 0% - 2% of amylose starch in glutinous rice is very complicated to detect. Therefore, if 5% or 10% japonica rice was mixed into glutinous rice, it is hard to detect it due to the amylose starch is still below 2%. In this paper, through the change of pasting properties of glutinous rice after mixing of different ratio of japonica rice, the setback value/degradation value （called impacting factor of japonica rice） is proposed as a supplementary data for qualitative identification to find out whether japonica rice is added. This method can solve the problem of using amylose starch content to judge whether the japonica rice was added into the glutinous rice.