Evaporative Cooling Systems for Perishables in Sub-Saharan Africa—A Review

Abstract

Postharvest food losses in the supply chain are currently estimated at 20% in the Sub-Saharan Africa region. In Sub-Saharan Africa, where the loss of fruits and vegetables can be particularly high, incorporating cold chain systems into value chains is an important strategy. Nevertheless, the absence of fundamental infrastructure and managerial expertise required to facilitate the advancement of cohesive cold chains, especially in rural regions, poses a substantial obstacle. Evaporative cooling has been suggested as an inexpensive cooling substitute for increasing the shelf life of fresh fruits and vegetables in hot, dry climates. Evaporative cooling is not a new concept; its use in buildings can be traced back thousands of years. However, renewed interest is spurring innovation in evaporative-cooling technologies. This comprehensive review explores the fundamental concepts and applications of different classes of evaporative cooling systems, with a particular focus on the preservation of postharvest quality of fruits and vegetables, and its economic implications. In addition, the review discusses the role of desiccant/dehumidification systems in improving the performance of evaporative cooling and furthermore presents a decision support system as a tool that promotes the effective use of evaporative coolers. The review underscores the potential of evaporative coolers as a viable solution for short-term postharvest preservation of horticultural produce. This system not only significantly lowers storage temperature, but also elevates the relative humidity within the storage environment, a critical factor in preserving the freshness and quality of the stored commodities. Thus, this paper presents a compelling case for the adoption of evaporative cooling technologies in the agri-food sector.