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

Olagunju et al. Food Production, Processing and Nutrition (2024) 6:32 https://doi.org/10.1186/s43014-023-00175-8 Food Production, Processing and Nutrition Open Access RESEARCH High‑protein, low glycemic index snack from optimized blend of three wholegrains exhibits nutraceutical quality and elicits low glycemic response in diabetic human subjects Aderonke Ibidunni Olagunju1* , Titilope Ifeolu Arigbede1, Idowu Sunday Oyeleye2, Solomon Akinremi Makanjuola3, Esther Taiwo Oyebode1 and Adenike Christianah Enikuomehin4 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 nondiabetics; 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. Keywords Multigrain, High-protein snack, Clinical observation, Glycemic regulation, Serum biochemical properties *Correspondence: Aderonke Ibidunni Olagunju Full list of author information is available at the end of the article © The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Olagunju et al. Food Production, Processing and Nutrition (2024) 6:32 Page 2 of 17 Introduction Diabetes mellitus (DM), which is regarded as the disease of the 2 1st Century, is a growing epidemic health problem, characterized by elevated blood glucose as a result of either insufficient insulin production by the pancreas or a result of ineffective use of the insulin produced (WHO 2021). Changes in global food systems, the increasing adoption of high caloric intake and low energy expenditure (sedentary lifestyle) have promoted the pervasiveness of obesity and type-2 DM (Hruby & Hu 2015). Improper management of DM has resulted in several macrovascular and microvascular blood vessels initiating nephropathy, ocular disorders, heart attack, stroke and eventually death (Petrie et al. 2018). Obesity and hyperlipidemia are key risk factors of DM, thus, weight management is an essential tool for effective diabetic care and its complications, including cardiovascular diseases such as blood pressure, arteriosclerosis, and glycemic control (Wing et al. 2011). ‘High protein’ foods contain above 11 g/100 g protein (Ministry of Food and Drug Safety 2019). Interestingly, increased protein intake through high-protein foods complemented with reduced carbohydrate intake has the potential to reduce plasma glucose levels of diabetic individuals (Gannon & Nuttall 2004). Diet as one of the lifestyle interventions for diabetes management cannot be over-emphasized. Several reports have shown the effectiveness of a high-protein plant regimen in reducing the prevalence of diabetes in human subjects, some of which are Malaeb et al. (2019) and Yang et al. (2021). In a similar fashion, low glycemic index foods are reportedly beneficial for blood glucose control (Ojo et al. 2018; Bai et al. 2021). Plant-based diets include products from legumes, whole grains, vegetables and fruits, are nutritious and economically sustainable with diverse product options. Whole grain comprising the bran and germ fractions possess outstanding nutritional and bioactive properties, conferring relevant health-promoting benefits to its consumers and is relevant in weight control (Calinoiu & Vodnar 2018). Globally, snacks are an important contributor to human’s daily energy intake (Smith & Whiting 2019). They are often regarded as junk foods but recently, snack products are evolving as new carriers of functional ingredients with nutritional and health-promoting benefits (Kim et al. 2020). Impressively, the potential of functional foods including functional snack products in controlling hyperglycemia or managing diabetes is being explored (Krawecka et al. 2019; Yang et al. 2021). The consumption of healthy snacks reportedly controls the rise in blood glucose levels while controlling the glycemic response of the subsequent meal (Imai et al. 2018; Graphical Abstract Olagunju et al. Food Production, Processing and Nutrition (2024) 6:32 Page 3 of 17 Nitta et al. 2019). The diet approach to the management and prevention of type 2 diabetes in some countries is remarkable (Hwalla et al. 2021; Rajput et al. 2022). The glycemic index (GI) measures the dynamics of hydrolysis and absorption of carbohydrates into the bloodstream whereas, glycemic load (GL) predicts the effect of amount of carbohydrate consumed per serving (Krawecka et al. 2019). Overall, both are rating systems to measure the promptness of foods to cause increase in blood glucose leve (...truncated)