The technology is called Dynamic Controlled Atmosphere (DCA) and while it has been used effectively in other regions of the world, such as with the post-harvest management of Canada’s commercial apple industry, it has not been used in New Zealand before.
Using sensor equipment, the technology continuously monitors within an air-tight environment (such as a refrigerated shipping container) and adjusts accordingly, to maintain a low oxygen atmosphere the container to a pre-programmed range.
This delays the maturation process and prevents the fruit from ripening while in transit.
Testing and research of Controlled Atmosphere (CA) technologies for the post-harvest management of Hass avocados has been underway for several years, with New Zealand researchers publishing early results on the benefits of this technology in the proceedings of the 5th World Avocado Congress, back in 2003.
But it wasn’t until a recent commercial trial by the NZ Government research institute, Plant and Food Researchand in association with NZ’sAvocado Industry Council (AIC), that the concept was proven on a commercial scale.
Two thousand trays of avocados (approx. 11,000kgs) were packed into shipping containers, fitted with Dynamic Controlled Atmosphere (DCA) equipment. This container was then exported to France in late December with distinct improvements in product quality upon arrival.
A number of international shipping lines have introduced and are now offering specialized shipping containers with Controlled Atmosphere capability.
Benefits to the New Zealand Avocado Industry
The New Zealand Avocado Growers’ Association Inc. (NZAGA)chief executive Jen Scoular says growers produced a record-breaking avocado crop this season, but exports to Australia did not go smoothly, which led to lower returns for the growers.
“Early in the season, Australia forecast their crop would be light because of adverse weather. But the actual crop out of Australia was significantly higher, so when New Zealand avocados arrived across the Tasman, their market was swamped and prices fell,” Scoular explained.
While Australia remains a very important market for the New Zealand avocado industry, Scoular indicated that “developing new export markets throughout Asia and even Europe must be given high priority”.
Some New Zealand avocado growers have called for a single-desk export system be established for the avocado industry, similar to the successful export model established by Zespri for international export of New Zealand kiwifruit.
However, this approach, where all export growers are required to export their produce under a single brand and marketing entity, is no longer possible under World Trade Organization rules, according to the NZAGA, as it is considered monopolistic and anti-competitive.
The industry’s goal had been to export 25% of this year’s crop to markets outside of Australia. But despite a successful push into Japan, volumes fell short of this target and reached just 19%.
Another container shipment, using the new Dynamic Controlled Atmosphere equipment, is currently on route to Honolulu and this will be followed with two further containers to France, which will help determine the ideal conditions required when transporting avocados for more than 20 days at a time.
It is hoped that this technology solution to the issue of rapid ripening and subsequent spoilage in transit will open niche market opportunities for the New Zealand avocado industry.