Digestion and fermentation of bionic grain-resistant corn starch and its effects on glucose response in mice

To address the rapid digestibility and nutritional imbalance of corn starch (CS), bionic grain-resistant corn starch embedded with gellan gum and soy protein isolate (CGS) was prepared by a co-encapsulation strategy to enhance enzymatic resistance and nutritional profile of CS. The proportion of resistant starch in cooked CGS increased from 9.3 to 22.6%. Structural characterization revealed that gellan gum formed a tight encapsulation structure with CS and soy protein isolate. Compared with CS, the CGS group in vitro fecal fermentation enhanced the yields of acetic, propionic, and butyric acids, and increased the abundance of Coprococcus comes, Bacteroides thetaiotaomicron, Prevotella copri, and Parabacteroides merdae by 17.6, 21.83, 3.17, and 6.68 times, respectively. Compared with CS, the CGS group exhibited a decrease in peak postprandial glucose from 11.98 to 9.58 mmol/L. This study offers a scientific foundation for creating starch-based foods to improve glucose metabolism disorders and promote intestinal health.