Wednesday, April 18, 2012

Food miles challenged



Shoppers can be misled about the carbon footprint benefits of buying locally-produced food.
The latest research is from the Commonwealth Scientific and Industrial Research Organisation of Australia, adding to earlier and similar research in the United Kingdom and North America.
More important than the distance food travels is how it is produced and how far shoppers drive to buy it, says Australia’s main research organization.
''Local food can often have a higher carbon footprint than food from afar,'' says principal researcher Brad Ridoutt.
He says even home-grown vegetables, with ''zero food miles'', do not necessarily have a smaller carbon footprint than those bought in the supermarket.
''With my veggies, I drive to Bunnings to buy fertiliser, and I go away for the weekend and forget to water them, and in the end I only harvest a few things that I can actually eat.
''By contrast, big producers, who can invest in the latest energy-efficient, water-efficient technology, and make use of all the parts of food, can be much more efficient,'' he says.
Of course, transporting food from producer to retailer still burns fossil fuels that release greenhouse gas emissions, in turn accelerating global warming. But freight emissions are only a fraction of those released during production, meaning even imported food, sustainably produced, can have a smaller carbon footprint than local alternatives.
The CSIRO research, focusing on farm and production emissions, as well as and other environmental impacts, should ultimately allow for comparisons between production and freight emissions.
The only Australian study to make this comparison was by Aldi and Planet Ark in in 2010. It found that a brand of Italian olive oil had a carbon footprint about 14 per cent smaller, per 100 millilitres, than that of a local brand, despite travelling about ten times as far, mainly because of its steel tin packaging and low-impact, traditional farm production.
British studies have also shown shoppers are likely to be responsible for fewer emissions if they buy organic fruit shipped from New Zealand, and beans air-freighted from manual farms in Kenya, rather than British equivalents grown in gas-heated greenhouses.
Peter Shawn Taylor, a columnist for the Waterloo Region Record, raised eyebrows two years ago when he wrote a column explaining why strawberries from California sold in local supermarkets have a lower carbon footprint than locally-grown strawberries.

Speaking Tuesday at Farm & Food Care’s annual meeting in Waterloo, David Smith, vice-president for sustainability for Sobeys Inc., said transportation averages less than two per cent of the total carbon footprint for products his supermarket chain markets.