Methods of reducing postharvest losses of roots, tubers, fruits, and vegetables in developing country economies

This report focuses on various storage and processing interventions designed to improve the postharvest production of fruits, roots, tubers, and vegetables. Of crucial importance to the shelf life and quality of produce are the temperature, relative humidity, gas concentrations, ventilation, and absence of light in the storage environment. Although refrigeration reduces spoilage of perishable produce, the dual need for equipment maintenance and a continuous power supply frequently limits its applicability in developing countries. Less expensive cooling systems and mechanical devices need to be developed such as those using freon, ammonia, or water. Evaporative cooling regulates humidity to prevent shriveling, a substantial problem in arid areas. Atmospheric gas alteration (AGA), also known as controlled atmosphere storage, places produce in an environment with air of different proportions of nitrogen, oxygen, and carbon dioxide. While AGA increases off-season fruit availability, fruit thus stored must be of higher quality than that stored in air to be cost-effective. An example of AGA preservation is the wrapping of bananas in semipermeable plastic film to trap carbon dioxide. Effective produce preservation also requires proper physical spacing and ventilation while in storage to combat fungal disease incidence. The pit storage method covers cured roots and tubers with dirt to maintain sufficient humidity and to shield the produce from the sun. Processing methods most applicable to LDCs" needs and of the greatest potential impact are easily implemented and are low in cost or labor intensive. Examples include ferm(-GO-TO-PAGE-)ng, dehydration, heat processing or canning, and chemical treatment. The report proposes further study of canning and fermentation processes. Attention should also be given to such vital factors as transportation, packaging (perhaps the cheapest method of minimizing produce losses), postharvest system analyses, and personnel training to ensure problem awareness. Four reference items (1970-78) are included.