Reconstituted Rice with Low-Glycemic-Index Potential as an Alternative to Polished Rice: Structural, Cooking,...

Polished rice is a global staple with a high glycemic index (GI), which makes it unsuitable for patients with diabetes. Functional rice reconstitution offers an effective technological approach for producing a low-GI nutritional staple. Konjac powder (KP), mulberry leaf extract (MLE), pueraria powder (PP), and resistant starch (RS) are functional ingredients that reduce the carbohydrate content of staple foods and attenuate postprandial blood glucose fluctuations. In this study, we developed three reconstituted rice formulations with low estimated glycemic index (eGI) using varying proportions of KP, MLE, PP, and RS, and investigated their nutritional composition, microstructure, cooking and textural properties, amino acid profile, volatile compounds, sensory quality, and in vitro starch digestibility. The functional ingredients increased dietary fiber and RS, formed a dense starch-colloid gel network with enhanced hydrogen bonding, improved cooking quality and texture, preserved the amino acid profile, enriched flavor, and achieved good sensory acceptability. Among the formulations, the MLE-high RS (MHR) formulation (80.0% rice, 9.0% KP, 0.5% MLE, 2.0% PP, and 8.5% RS) exhibited the lowest eGI as determined via in vitro digestion. Overall, this study provides theoretical and technical support for the development and industrial application of functional reconstituted rice with reduced starch digestibility.