Effect of weak alkaline electrolyzed water on rice cooking: Promoting rapid water absorption and enhancing the quality and digestibility

Abstract

Promoting the rapid water absorption of rice is beneficial for increasing the cooking quality and digestibility of rice. Under the action of an electric field, weak alkaline electrolyzed water (WAEW) had a smaller cluster system compared to tap water, with a 17.30% decrease in DDAA-OH (double donor-double acceptor) and a 22.89% increase in Free-OH. Therefore, there were fewer hydrogen bonds formed between water molecules, resulting in more free proton donors and proton acceptors, which increased the possibility of forming more hydrogen bonds with other substances. During the soaking process, WAEW could effectively increase the water absorption rate, maximum water content, and water diffusion rate in different types of rice. As WAEW formed more hydrogen bonds with substances in the rice, it was easier to combine with substances in the rice, forming more bound water. Under the combined effect of the alkaline environment of WAEW and the characteristics of its own water molecules, the surface and internal structure of the rice were eroded, the surface layer was peeled off, and a large number of pore structures were formed. Along with the increased water absorption, more substances such as starch and protein dissolved from the rice. The cooked rice soaked in WAEW had greater sensory quality, higher digestibility and glycemic index. Therefore, WAEW could be used as a new method for cooking rice, promoting the rapid absorption of water and increasing the sensory quality and digestibility.