Proximate composition and β-carotene-derived vitamin A potential of orange-fleshed sweet potato (OFSP) products from selected South African cultivars

Vitamin A deficiency (VAD) is widely recognised as a major public health problem in sub-Saharan Africa (SSA). Orange-fleshed sweet potato (OFSP), rich in β-carotene, offers a sustainable food-based intervention strategy to address VAD. However, the nutritional contribution of OFSP products depends on cultivar characteristics, formulation and processing methods, which influence proximate composition and carotenoid retention. This study evaluated the proximate composition and β-carotene of various OFSP-products developed from South African sweet potato (SP) cultivars (Khumo, Bophelo) and USA cultivar Beauregard. Four OFSP products, including flakes, instant porridge, crisps and pasta, were developed, and proximate composition, β-carotene content and retinol activity (RAE) were determined. The contribution of each product to the recommended dietary allowance (RDA) for vitamin A was calculated across different age groups. Statistically significant differences ( p < 0.001) were observed among OFSP-products. Moisture content ranged from 5.15 ± 0.03 to 9.68 ± 0.17%, protein from 2.18 ± 0.01 to 15.37% and fat from 0.74 ± 0.12 to 29.14 ± 0.29%. Carbohydrate was the major macronutrient, with energy values between 1527 ± 2.0 and 2113.3 ± 0.57 kJ/100 g. Furthermore, β-carotene ranged from 7.52 ± 0.09 to 22.56 ± 0.65 mg/100 g, equivalent to RAE values of 626.94 ± 7.87 to 1880.0 ± 54.16 µg/100 g. OFSP crisps retained the highest provitamin A, while instant porridge and pasta provided a balanced macronutrient profile due to composite formulation. This study demonstrated that 100 g of serving of OFSP flour or puree-based products could supply 100% of the vitamin A of RDA for children between 1 and 3, 4–8 and 9–13 years and pregnant women. These findings demonstrated that properly formulated OFSP products can serve as an effective, culturally adaptable vehicle for improving vitamin A intake and enhancing nutritional security.