Potential causes of postharvest losses, low-cost cooling technology for fresh produce farmers in Sub-Sahara Africa

摘要

The aim of this review was to identify the causes of postharvest losses (PHL) in fruit and vegetables in relation to small-scale farming in sub-Saharan Africa (SSA). The reduction of PHL can improve food security at household level. Farmers involved in small-scale production of fresh produce experience high PHL due to physiological deterioration associated with technical, biological and environmental factors and lack access to postharvest facilities. When these factors are contained, sufficient supplies of fresh produce reach the consumer and improve nutrition, income and food security at household level. This article described the PHL experienced by farmers along the cold chain and explored the advantages and disadvantages of the use of various cooling technologies. There are already existing modern cooling technologies but these are capital intensive and require electricity, which is not always available to small-scale farmers (SSF). This review proposes evaporative cooling as appropriate for SSF in SSA as it has proven to be effective under hot and dry areas and is a simpler and cheaper technology. The review recommends that with the incorporation of a desiccating unit, evaporative cooling could be extended to hot and humid areas. Solar and wind energy can be used to power the desiccating unit in remote and isolated areas with no access to grid electricity. Therefore, research needs to be carried out on developing or adapting a solar or wind powered evaporative cooling system under both hot-dry and hot-humid conditions.