Effects of Selenium Application on Starch Structure, Physicochemical Properties, and Texture Properties of Rice

The consumption of selenium-enriched rice represents an effective approach for human selenium intake. However, the potential effects of selenium on rice texture after cooking and the physicochemical properties of rice starch remain insufficiently understood. In this study, four selenium-enriched rice varieties and one conventional rice variety were selected to compare their nutritional components and eating quality and to investigate the microstructure and physicochemical properties of their starches. The results showed that selenium content in selenium-enriched rice was significantly higher than that in conventional rice (p < 0.01). Selenium enrichment had a positive effect on selenium accumulation, thereby promoting protein synthesis, with protein content increased by 3.01%-9.4%. However, it should be noted that the eating quality of selenium-enriched rice was inferior to that of conventional rice, as indicated by lower taste values. Compared to conventional rice, the resistant starch content of selenium-enriched rice increased by 13.41%-19.95%, the crystallinity increased by 4.89%-9.14%, the ordered double-helical structure of starch granules was enhanced, and the gelatinization temperature increased. This study provides a theoretical reference for the processing, product development, and quality improvement of selenium-enriched rice.