Nutritional Composition And In Vitro Starch Digestibility Of Crackers From Pearl Millet And Wheat Composited With Mushrooms

ABSTRACT

Type 2 diabetes is a global problem that can be controlled by a diet that consists of carbohydrates with substantial amounts of slowly digestible starch amongst others. Pearl millet (Pennisetum glaucum (L) R. Br.) is an underutilised cereal crop that in recent times, raised interest due to its health benefits. The low starch hydrolysis rate of pearl millet is particularly of interest in type 2 diabetes modulation. To contribute to the value-addition and food diversification using pearl millet, this project investigated the nutritional content and starch digestibility of composite flours and crackers made of pearl millet-wheat, truffle (Kalaharituber pfeilii) and Oyster mushroom (Pleurotus ostreatus) composite flours and crackers. Equal amounts of fermented whole pearl millet grain and bread wheat flour were mixed. Of this mixture, 5%, 10% and 15% were substituted with Oyster mushroom and Kalahari truffle powders. The moisture, fat, protein, ash and minerals contents, water absorption (WAI) and water solubility (WSI) indices, total starch and starch digestibility of the flour formulations and the resultant crackers were determined. The consumer acceptance of the composite crackers was also assessed. The ash content, WSI and WAI were higher in the mushroom flours than in the cereals composite flours. Contrary, mushroom containing flours had the lowest starch content of all the flours. For crackers, ash content, WAI and WSI were directly proportional to the levels of mushroom incorporation. In terms of consumer acceptance, 5% oyster mushroom and 5% Kalahari truffle incorporated crackers scored the highest on the 9 point hedonic scale. Starch digestibility of mushroom incorporated flours and crackers were lower than those of cereal composite products. The higher the mushroom incorporation level, the slower the glucose release rate, showing that mushroom incorporation may be beneficial to people with type 2 diabetes.