Reducing Postharvest Losses in Plantain through Sodium Alginate/Essential oil coatings

Abstract

Matured plantain fruits undergo postharvest physiological deterioration in the food supply chain contributing to food loss/waste and economic losses. However, available plantain preservation techniques are ineffective, cost intensive and unsustainable. The aim of the study was to evaluate effective, low-cost, and sustainable plantain preservation techniques by harnessing the potential of sodium alginate and cellulose nanocrystals to produce a film blended with cinnamon essential oil in varying proportions (10%, 15%, and 20%) and to determine the extended shelf-life of fresh plantain under the tested treatment conditions. The film produced exhibited good molecular interaction and thermal stability as elucidated by the Fourier Transform and Infrared (FTIR) spectroscopy and thermogravimetric analysis respectively. The samples of plantain coated with film-forming solution and stored up to 8 days were examined for their physiochemical parameters (pulp moisture content, oBrix, weight loss, firmness, and colour changes) during eight-day storage at room temperature (25 ±1°C). There was a significant (p<0.05) reduction in moisture production, oBrix, weight loss rate, and softening rate for coated plantains relative to the uncoated samples. Increasing proportion of the essential oil in the film was effective in delaying the unset of ripening and deterioration by one week. Therefore, by optimizing the level of cinnamon essential oil in the film, this innovative technique can serve as an effective, sustainable and inexpensive way of preserving plantain to maintain it nutritional and functional qualities while enhancing its economic value in the food supply chain.