High-protein, low glycemic index snack from optimized blend of three wholegrains exhibits nutraceutical quality and elicits low glycemic response in diabetic human subjects

Abstract Snack products are evolving as new carriers of functional ingredients with nutritional and health-promoting benefits. A blend of whole grains is increasingly being utilized to harness the functional potential of the grain mix. Amaranth, acha, and pearl millet grains flours were optimized using response surface methodology (RSM), to obtain optimum blends (90:5:5 and 47.98:26.68:25.34) with high protein content and low glycemic index. Snack bar products from the blends were labelled MBY and MBZ. A total of 40 diabetic and 10 non-diabetic subjects were recruited. Of the diabetic, about 42% were overweight while 40% were obese, the non-diabetic had normal weights. Each was allowed to consume snacks containing the equivalent of 50 g of carbohydrates. Finger prick was employed to evaluate the postprandial glucose response of snack products while venous blood was evaluated for antioxidant enzymes, carbohydrate-hydrolyzing activities, and insulin using standard methods. Consumption of the multigrain snacks elicited a stable postprandial response (133–141 mg/dL) with 16 and 24% postprandial decline. In addition, snacks had low to intermediate glycemic index (52 and 56) in diabetic and low glycemic index (43 and 45) in non-diabetics; likewise reduced α-amylase/α-glucosidase activities compared to control snacks. Similarly, glutathione level, glutathione peroxidase, superoxide dismutase, and catalase activities in serum from subjects that consumed multigrain snacks were upregulated compared to control and market sample groups. Moreso, snack products promoted a reduction in serum insulin levels in diabetic subjects (45 and 17% for MBY and MBZ respectively). Following the nutraceutical properties displayed by the formulated snack especially MBY, it can be promoted as a functional snack for the management of diabetes while solving the limited snack product choice of diabetes sufferers. Graphical Abstract