Minerals, vitamin C, and effect of thermal processing on carotenoids composition in nine varieties orange-fleshed sweet potato (Ipomoea batatas L.)

Abstract

Micronutrient malnutrition is a major global health problem, which affects in excess of 2 billion people in developing countries. This study, aimed at promoting plant-food-based approaches to tackle micronutrient deficiency, reports the mineral and vitamin C contents, and carotenoid composition (β-carotene, α-carotene, lutein, lycopene and β-cryptoxanthin) of nine varieties of orange-fleshed sweet potato (OFSP). The studied OFSP varieties exhibited significant variation in analyzed nutrient content. Among the selected varieties, BARI SP8 (6710.50 ± 43.79 μg/100 g) contained the highest concentration of β-carotene, while BARI SP6 (230.40 ± 11.94 μg/100 g) contained the lowest concentration of this substituent. Besides β-carotene, significant amounts of vitamin C, minerals, and lycopene were found in the selected OFSP varieties. Boiling of the OFSP samples resulted in significant reduction of carotenoids, ranging from 22 % to 78 % for β-carotene, 38 %–96 % for lycopene and 79 %–100 % for β-cryptoxanthin. None of the studied OFSP varieties were found to contain α-carotene and lutein. The principal component analysis (PCA) of analyzed variables divided the OFSP varieties into four clusters, and the first two principal components explained about 72.57 % of the total data set variance. Thus, being rich in minerals, vitamin C and β-carotene, the studied OFSP varieties could be utilized as a promising source of dietary micronutrients to reduce or prevent the vitamin A malnutrition and other micronutrient deficiency-related diseases observed in affected populations.