In-transit ripening and prediction of outturn quality for mango (MG12016)

What was it all about?

This project investigated the feasibility of in-transit ripening, where mangoes are cooled and transported at 18°C. This would reduce cold room requirements at the pack house and energy costs during cooling and transport as well as reducing time needed to ripen the produce. For in-transit ripening to be effective, good fruit temperature management and ethylene and CO2 control are required.

Components of the project were…

• Testing technologies to record fruit temperatures and CO2 and ethylene concentrations during the 2-4 day refrigerated road trip of mango fruit from the Northern Territory to southern markets
• Developing and testing systems for releasing ethylene gas into the refrigerated container and for minimising CO2 accumulation during transit
• Developing decision aid tools that will estimate the behaviour of the fruit during transport based on the recorded temperature, ethylene and CO2 concentrations and help the ripener to determine the additional days needed to ripen the fruit to the stage required by the retailers
• Undertaking semi-commercial testing of these technologies in selected mango supply chains.

The main outcomes of the work were…

• Systems for slow release of ethylene were developed from an Australian-developed ethylene releasing powder called Ripestuff
• Techniques for absorbing CO2were developed using hydrated lime
• Tests with commercial consignments from the NT to Brisbane confirmed that ethylene and CO2 concentrations can be successfully maintained for the journey
• Ripe fruit quality was maintained.

Next steps in developing the process were to reduce the application costs of ethylene and CO2 management and to develop systems for maintaining oxygen concentrations above levels that will not impede ripening. More cost-effective means for monitoring ethylene concentrations are also required.