Kiwifruit marketer Zespri has tracked the carbon lifecycle of its produce from the orchard to the consumer in Europe in response to a British climate change study that named the fruit as a global-warming offender.
The 2006 report on "food miles", by former World Bank economist Sir Nicholas Stern and commissioned by the British Government, cited the kiwifruit trade as a contributor to environmental damage and had local Wellington leaping to the defence of New Zealand's long-distance exports.
The study estimated that flying 1kg of kiwifruit from New Zealand to Europe causes 5kg of carbon to be discharged into the atmosphere.
But Zespri, which exports 60 per cent of its overseas kiwifruit produce to Europe, challenged the veracity of the study because its fruit all goes to Britain by ship.
Yesterday, it released the results of its own research - commissioned in 2007 - assessing its carbon footprint across each part of the supply chain.
The study, undertaken by Landcare Research and funded by the Ministry of Agriculture and Forestry, showed shipping accounted for the most carbon emissions for all European exports at 41 per cent.
Consumer consumption and disposal made up 22 per cent, orchard operations were 17 per cent, packhouse and coolstore processes account for 11 per cent of total emissions and repacking and retailer were 9 per cent.
Zespri sustainability manager Glen Arrowsmith said the company's research put the British study into context.
"If you just look at the shipping of a product, actually a significant amount of the emissions are at other stages of the chain such as the production or the cool storage. Around about 22 per cent of the emissions are actually at the consumer end in terms of driving to the supermarket, getting the product, consuming the product and disposing of it."
The company had employed several initiatives to reduce carbon emissions including using slow-steaming ships, which reduced diesel use by 17 per cent, Mr Arrowsmith said
Zespri was also working with shipping company SkySails, which has developed a kite-type sail fitted at the front of existing cargo ships to harness the wind's energy and propel the vessel.
It is flown at an altitude of 100m to 300m off the front of a ship and depending on wind conditions can reduce average fuel costs by between 3 and 10 per cent, with temporary fuel cuts of up to 50 per cent in optimal conditions.
Mr Arrowsmith said Zespri had also recently changed its packaging to allow a greater quantity of kiwifruit to be shipped at one time.
Turning kiwifruit waste into bio-plastics for packaging and reducing waste were other initiatives.
The Minister of Agriculture and Forestry, David Carter, said the study would "set in place changes that will ensure New Zealand retains a global leadership position in sustainability".
Kiwifruit carbon emissions*
Shipping - 41 per cent.
Consumer consumption and disposal - 22 per cent
Orchard operations - 17 per cent.
Packhouse and coolstore processes - 11 per cent.
Repacking and retailer - 9 per cent.
* Zespri figures for each stage of the lifecycle based on produce destined for Europe.