ETHYLENE RIPENING PROTOCOLS FOR LOCAL AND EXPORT MARKET AVOCADOS

Due to consumer demand there is an increasing requirement for the industry to provide a ripe to eat product. Although developed in California over a decade ago, there remain a number of issues in carrying out ethylene treatment ("pre-ripening") which need to be understood to provide a consistent, high quality product. We have examined a number of variables in the ethylene treatment and handling of avocados with the aim of optimising current industry practices for local and export market fruit. In addition we have sought to develop protocols where ethylene treatment is carried out in NZ at either 17°C or 5.5°C prior to export of fruit. Experiments have been carried out examining; fruit maturity/time of harvest, treatment duration, treatment temperature, post-treatment holding duration, and final storage temperature. From this work we have made a range of recommendations such as minimum treatment durations for two harvest times in the season for non-stored (local), and stored (export) fruit. Storage temperatures lower than 4°C are not recommended due to reduced fruit quality, particularly external chilling injury. We have questioned the need to ethylene treat fruit which have bee