Reducing skin damage and improving postharvest efficiency of Calypso mango (MG10008)

What was it all about?

Calypso mango is a successful variety, with many desirable qualities that meet the needs of Australian retailers. It also has excellent export potential into Asian, Middle Eastern and European markets. This project funded a series of research streams to maximise opportunities for Calypso growers.

The study included work to…

• Improve external appearance for export markets requiring irradiation against fruit fly and other quarantine pests, particularly extensive lenticel discolouration
• Evaluate the feasibility of in-transit ripening, which would produce cost advantages by:

o Reducing floor space for on-farm precooling and in-market ripening

o Reducing the time from harvest to market allowing access to higher prices at the start of the season

o Reducing energy requirements by not cooling the fruit as much on-farm, running the trucks at higher temperatures, and not requiring warm-up of fruit in market before ripening. 


• Extend the harvest window to reduce the intensive labour requirements
• Investigate alternative systems of moving fruit from the tree to the holding bin on farm.

Key findings were…

• Lenticel discolouration varies significantly across locations and seasons
• Withholding irrigation to avoid water damage increased the development of lenticel discolouration
• Bagging the fruit with paper and spraying with a carnauba-based wax before harvest reduced discolouration in the ripe fruit but the wax treatment needs commercial testing
• The most promising approaches to reduce discolouration were eliminating water from the harvesting and packing procedures, and irradiating near ripe fruit, though the impacts of these treatments on the whole chain needs to be considered
• The most promising ways of moving fruit from trees was to use six bin runners and possibly larger harvest aids that can deposit the bin directly onto flatbed trucks
• Commercial tests of in-transit ripening indicated that while the new 12 metre rail containers can retain mango fruit temperatures at about 18oC, temperature management can be negatively affected by loading warmer fruit, and poor loading practices that disrupt air circulation in the containers
• Carbon dioxide concentrations in these containers can be controlled with hydrated lime as long as fruit temperature is controlled, and several systems for slow release ethylene in transit showed promise.