Pg. 32-36 Research on Alternatives to Post-Harvest Sulphur Fumigation of Litchi Fruit

A study is being conducted, of which the main aim is to develop a suitable alternative to the currently used sulphur fumigation process. Evaluation of the pericarp colour retention and anti-fungal properties of a range of organic acids revealed that a tartaric acid treatment might possibly serve the purpose. Refinement of the treatment should include evaluations on the use of tartaric acid combinations and less concentrated applications. It was a/so found that dipping the fruit in a hot water solution containing imazalil might be effective. Combining the lmazalil treatment with an acid dip should, however, be further investigated. Additional post-harvest procedures, namely hydrocooling, modified atmosphere storage and ventilationrestricting boxes did not seem to have practical application in the South African litchi export industry. Further research will concentrate on optimizing the organic acid treatments.