{"title":"Multiple effects of oil addition and freezing-reheating treatment on the in vitro starch digestibility of rice grains","authors":"Masatsugu Tamura , Yukari Saito , Takahiro Saito , Hideaki Kobayashi , Akifumi Mikami , Yoshimasa Sasahara","doi":"10.1016/j.fhfh.2023.100150","DOIUrl":null,"url":null,"abstract":"<div><p>The objective of this study was to investigate the multiple effects of the addition of oils and freezing-reheating treatment, which are characteristics of frozen rice, on the starch digestibility of rice grains. Either rapeseed oil or its emulsifier was added to the polished grains at a weight ratio of 1.2%, stirred, and cooked. Cooked grains were frozen, stored in a freezer at -20 °C, and reheated in a microwave oven to prepare frozen-reheated grains. While the equilibrium concentration of starch hydrolysis (C<sub>∞</sub>) was significantly higher for frozen-reheated grains (98.30%–110.92%) than for cooked grains (95.35%–97.91%), the kinetic constant (k) was significantly lower for frozen-reheated grains (7.39 × 10<sup>−3</sup>–8.98 × 10<sup>−3</sup> min<sup>−1</sup>) than for cooked grains (9.16 × 10<sup>−3</sup>–9.45 × 10<sup>−3</sup> min<sup>−1</sup>). The eGI ranged from 86.42 to 89.98 and was not significantly affected by the addition of oils, freezing-reheating, or the interaction. The results suggested that C<sub>∞</sub> and k of rice grains was not affected by the addition of 1.2% of oils and interaction but was affected by freezing-reheating.</p></div>","PeriodicalId":12385,"journal":{"name":"Food Hydrocolloids for Health","volume":null,"pages":null},"PeriodicalIF":4.6000,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Food Hydrocolloids for Health","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2667025923000341","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
The objective of this study was to investigate the multiple effects of the addition of oils and freezing-reheating treatment, which are characteristics of frozen rice, on the starch digestibility of rice grains. Either rapeseed oil or its emulsifier was added to the polished grains at a weight ratio of 1.2%, stirred, and cooked. Cooked grains were frozen, stored in a freezer at -20 °C, and reheated in a microwave oven to prepare frozen-reheated grains. While the equilibrium concentration of starch hydrolysis (C∞) was significantly higher for frozen-reheated grains (98.30%–110.92%) than for cooked grains (95.35%–97.91%), the kinetic constant (k) was significantly lower for frozen-reheated grains (7.39 × 10−3–8.98 × 10−3 min−1) than for cooked grains (9.16 × 10−3–9.45 × 10−3 min−1). The eGI ranged from 86.42 to 89.98 and was not significantly affected by the addition of oils, freezing-reheating, or the interaction. The results suggested that C∞ and k of rice grains was not affected by the addition of 1.2% of oils and interaction but was affected by freezing-reheating.