TITLE:
Mineral Composition of Tropical Fruits: Banana (Musa spp.), Mango (Mangifera indica), Pineapple (Ananas comosus) and Watermelon (Citrullus lanatus)
AUTHORS:
Clare Kwamboka Riose, Grace Lagat, Pius Kipkemboi
KEYWORDS:
Tropical Fruits, Mineral Composition, Fruit Fractions, Peel Valorisation, AOAC, Atomic Absorption Spectrophotometry (AAS), ANOVA
JOURNAL NAME:
Open Access Library Journal,
Vol.13 No.10,
October
30,
2026
ABSTRACT: Tropical fruits contribute substantially to human mineral intake, yet most nutritional studies focus narrowly on the edible flesh and overlook the mineral contribution of peels and seeds, fractions routinely discarded as waste. This study determined the mineral composition of the flesh, peel and, where applicable, seed fractions of four tropical fruits commonly consumed in Kenya: banana (Musa spp.), mango (Mangifera indica), pineapple (Ananas comosus) and watermelon (Citrullus lanatus). Twenty mature fruits of each species were sourced from retail markets in Eldoret, Uasin Gishu County, separated into their respective fractions, oven-dried, ground and analysed for potassium, zinc, calcium, magnesium and iron using Atomic Absorption Spectrophotometry following dry-ashing, in accordance with AOAC protocols. Potassium emerged as the dominant mineral across all samples, reaching its highest concentration in banana peel (66.84 mg/100g), while iron occurred at generally low concentrations throughout. Banana recorded the highest mean potassium (52.08 mg/100g) and zinc (9.80 mg/100g) content among the four fruits, whereas mango recorded the highest mean magnesium (9.85 mg/100g) and iron (4.73 mg/100g) content. Watermelon showed the lowest concentrations across most minerals examined. Across all four fruits, peel fractions consistently accumulated higher concentrations of potassium, zinc, calcium and magnesium than flesh, while seed fractions carried the highest iron content. One-way ANOVA revealed no statistically significant differences in mineral composition among the four fruit species (p = 0.1698) or among the three fruit fractions (p = 0.4623) at the 95% confidence level. These findings indicate that peel and seed fractions retain mineral concentrations comparable to, and in several cases exceeding, those of the edible flesh, positioning them as viable candidates for valorisation into flour, animal feed or nutraceutical products rather than continued disposal as agricultural waste.