AUSTRALIA'S first formal system of carbon labelling will be introduced today - and it has already revealed that olive oil imported from overseas has a similar carbon footprint to oil made from olives grown here.
The budget retailer Aldi engaged the environment group Planet Ark and the British Carbon Trust to do measurements that traced oil home to its native groves in Italy and Australia.
Although imported oil registers much higher ''food miles'', meaning more energy has to be spent shipping it to Australia, this was generally offset by more traditional farming practices in Europe. Most of the greenhouse gas emissions generated by food occur during the farming, not when the products are shipped to supermarkets, the study found.
Aldi will label all its oils on a comparative scale so shoppers can make informed choices, with other large retailers watching to see how it affects sales.
''I think it's fair to say that the process of measuring was more involved and more complex than they expected it to be,'' said Planet Ark's carbon labelling manager, Diane Mann. ''The key to each particular carbon footprint is the full life cycle of a product, not necessarily how far it has travelled.''
Remano brand pure and extra virgin olive oils, which are sold in four-litre bottles, had the smallest carbon footprint of any of the oils labelled, with 220 grams of carbon dioxide emitted for every 100 millilitres of oil on the supermarket shelf. This means using 100 millilitres of the oil is roughly equivalent to driving a car for one kilometre, in terms of carbon emissions.
An Aldi spokesman said the labels would not cost customers more money.