Combining high-carbohydrate food with polyphenol-rich food is a possible way of producing slowly digestible starch with beneficial health properties. In Japan, non-glutinous and glutinous rice are cooked with adzuki bean and the colour of the cooked rice is pale red. In this article, we show that (1) the red colour of rice could be attributed to the oxidation of adzuki bean procyanidins, (2) pancreatin-induced starch digestion of the red-coloured non-glutinous rice was slower than white rice and (3) the digestion of amylose and potato starch but not amylopectin became slower by heating with procyanidin B2. Furthermore, the rate of starch digestion of red-coloured rice was not affected by nitrite treatment under simulated gastric conditions. The above results show that procyanidins could bind to amylose independent of the starch source by heating and could suppress starch digestion by α-amylase in the intestine.

将高碳水化合物食物与富含多酚的食物结合在一起是生产具有有益健康特性的缓慢消化淀粉的一种可能方法。在日本，非糯米和糯米都是用红豆煮的，米的颜色是淡红色。在本文中，我们表明（1）水稻的红色可能归因于小豆原花青素的氧化;（2）胰酶诱导的红色非糯米的淀粉消化速度比白米慢，并且（ 3）通过与原花青素B2一起加热，直链淀粉和马铃薯淀粉的消化速度变慢，但支链淀粉的消化速度变慢。此外，在模拟的胃部条件下，亚硝酸盐处理不会影响红色大米的淀粉消化速率。