Effects of Small-scale Processing on Shelf Life, Vitamin A Retention, and Sensory Acceptability of Mango, Orange-fleshed Sweet Potato, and Pumpkin in Northern Sierra Leone
Beatrice Edwina Koroma *
Department of Public Health, Njala University, Njala, Sierra Leone.
Richards Wadsworth
Department of Biological Sciences, Njala University, Njala, Sierra Leone.
Alhaji Brima Gogra
Ernest Bai Koroma University of Science and Technology, Makeni, Sierra Leone.
Mohamed Kemoh Rogers
School of Public Health, Njala University, Bo, Sierra Leone.
Sylvia Karcher Bangura
Ernest Bai Koroma University of Science and Technology, Makeni, Sierra Leone.
Mohamed Ambrose Koroma
Eastern Technical University of Sierra Leone, Kenema, Sierra Leone.
Alhaji Tamu Bockarie
Eastern Technical University of Sierra Leone, Kenema, Sierra Leone.
*Author to whom correspondence should be addressed.
Abstract
Micronutrient deficiency, particularly vitamin A deficiency, persists among women and young children in rural Sierra Leone despite the local availability of nutrient-rich indigenous foods, whose dietary contribution is constrained by extreme seasonality, high perishability, and low acceptability of raw forms. This study evaluated how simple, community-level processing affects the vitamin A content, shelf life, and sensory acceptability of three locally available species — mango (Mangifera indica), orange-fleshed sweet potato (OFSP; Ipomoea batatas), and pumpkin (Cucurbita spp.) — in Bombali and Tonkolili Districts, Northern Sierra Leone. The core process was controlled low-temperature drying (solar and cabinet) of all three species into shelf-stable snacks; two blended products were additionally formulated, namely mango juice and a pumpkin–mango purée intended as a complementary food, which is why two final products were derived from three raw materials. Shelf life was defined as the number of days a product remained organoleptically acceptable under ambient storage. Vitamin A content was estimated from food-composition baselines adjusted by published nutrient-retention factors; acceptability was rated by a community sensory panel on 5-point and 9-point hedonic scales, and qualitative data from focus group discussions and key-informant interviews were analysed thematically. Processing extended mean shelf life more than tenfold (6.1 to 66.4 days) while reducing estimated mean vitamin A by 12.1% (701 to 616 µg). Acceptability rose significantly for all three product types (p < 0.001; Cohen’s d = 0.32–0.37), and the two final products achieved high willingness-to-consume (mango juice 78%; purée 64%). The large gains in availability and acceptability outweigh the modest vitamin A loss; because the loss was sensitive to drying conditions, controlled low-temperature drying could narrow it further. These findings support embedding low-cost processing in nutrition programming for vulnerable rural populations.
Keywords: Underutilised species, vitamin A retention, provitamin A carotenoids, orange-fleshed sweet potato, pumpkin–mango purée, mango juice, shelf-life extension, low-temperature drying, sensory acceptability, Sierra Leone, community-level processing, complementary food