Overview

Women carry out most production of horticultural crops in Tanzania and other developing countries. Harvest periods are short but less than 1% of the crop is processed for off-season consumption. Previous attempts at establishing solar drying have been unsuccessful due to their expense, low throughput capacity and inability to operate in cloudy environments.

Concentrated solar power (CSP) utilizes reflective surfaces to increase solar heat gain. CSP is less expensive than glazed solar collectors but has never been applied to food drying. It may also improve dried product color and color retention without addition of sulfites, improve texture, nutrient retention and rehydration properties and therefore will add value to the product, reduce the current 50-80% postharvest loss and increase product value.

This project designs and tests a batch CSP dryer for mangoes and tomatoes in simulated cloudy environments. CSP will be evaluated in terms of drying efficiency, cost and product quality.