Nutritional, Functional, and Mineral Properties of Composite Flour from Orange-fleshed Sweet Potato and Mushroom (Pleurotus tuberregium Sclerotium)
Eunice Olunike Oyelade *
Department of Food Science, Ladoke Akintola University of Technology, Ogbomoso, Nigeria.
Bolanle Aishat Akinwande
Department of Food Science, Ladoke Akintola University of Technology, Ogbomoso, Nigeria.
Alice Oluwatobi Adegbite
Department of Food Science, Ladoke Akintola University of Technology, Ogbomoso, Nigeria.
Rachel Oluwatoyin Adetola
Department of Food Science, Ladoke Akintola University of Technology, Ogbomoso, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
The increasing demand for micronutrients to address deficiencies and the worldwide transition to functional foods have made nutrient-enriched flours from underutilized crops a matter of great concern. Orange-fleshed sweet potato (OFSP) contains high levels of beta-carotene (provitamin A), and Pleurotus tuberregium is a good source of dietary fiber, protein, and vital minerals. The composite flour containing OFSP and P. tuberregium sclerotium were formulated in ratio 100:0, 85:15, 80:20, 75:25, 70:30, 65:35 and 100% yellow maize as control. To aid the development of nutrient-rich functional foods, this study examined the proximate composition, functional properties, and mineral content of composite flours and the control sample. A simplex lattice design was employed to prepare composite blends at varying proportions, including 100% OFSP and yellow maize as control samples, which were subsequently analyzed using standard analytical procedures. Proximate analysis revealed moisture (0.38-0.94%), fat (0.93-1.32%), ash (1.62-3.68%), crude fiber (2.50-5.59%), protein (14.20-21.90%), and carbohydrate (67.10-78.88%). The addition of more mushrooms progressively increased protein, fiber, and ash levels. Functional property analysis revealed water absorption capacity (221.00-252.33%), swelling capacity (6.14-9.51%), solubility index (18.33-34.23%), oil absorption capacity (121.00-162.00%), and bulk density (0.53-0.61 g/cm³), which are suitable for various food formulations. The mineral result showed appreciable levels of potassium (222.30-502.57 mg/100 g), calcium (132.68-198.58 mg/100 g), magnesium (110.36-197.81 mg/100 g), and iron (1.17-2.55 mg/100 g). These findings reveal complementary nutritional and functional interactions between OFSP and P. tuberregium sclerotium, indicating that they can be used as health-promoting components in functional foods to enhance protein consumption and reduce micro-deficiencies in susceptible populations.
Keywords: Functional meal, micronutrients, minerals, mushroom, nutrition, potato