Food miles are the distance food has travelled from its point of origin to you. In America, retail experts calculate that the average distance for any one item of food is around 1,100 miles. The contents of the average European shopping trolley travel 2,200 miles.

Food miles are a modern phenomenon and are part of the supermarket revolution. More than a third of the food we eat these days in Britain is imported. This produces an elongated food chain involving numerous intermediate links - processors, packers, hauliers - between producer and consumer. Such links inevitably push down the prices to producers and push up the prices for consumers.

Not only is our food travelling further but we are buying it in fewer, larger outlets controlled by a handful of retailers. The big five - Sainsbury, Tesco, Safeway, Asda and Gateway - take 70 per cent of Britain's entire grocery sales. According to the Institute of Grocery Distribution, 2 per cent of Britain's superstores now account for 37 per cent of the nation's grocery business.

This Friday in London, the Soil Association (the body that promotes organic farming) is holding a conference on 'Food, Farming and Society: Towards a New Model'. The association argues that despite the apparent wide choice, diversity - both market and biological - is actually decreasing. Every food mile, it points out, costs the environment in fossil fuel, carbon dioxide, other greenhouse emissions and ozone-depleting refrigerants, since cold storage is an integral part of the international food business.

'We are not against supermarkets per se. In fact, we recognise that they have been responsible for much of the growth in organic farming to date. But we need viable alternatives in the form of local, direct, producer-consumer food retailing schemes,' says Patrick Holden, a member.

Britain's organic farmers and growers have been developing non-supermarket avenues for retailing their food, all under the rubric of Community Supported Agriculture. Such localised food supply schemes are already widespread in the USA, and in European countries such as Switzerland and Germany.

The most familiar model is the farm shop. Another idea, borrowed from Japan, is consumer co-ops where customers group together to buy from producers who pool and deliver their produce. Then there are 'box' delivery schemes, where a grower shares out his or her produce among a list of regular takers. A more elaborate version is the subscription system, where the grower prepares a budget and projected yield for the season and offers 'shares' in advance. Shareholders then 'own' the harvest which is delivered to them weekly.

'The new focus should be locally produced food first and foremost. Imports from faraway places would then become a useful top-up or second string, not a substitute,' says Mr Holden.

One such scheme is a home-delivery 'box' scheme run by Jan Deane with the produce from her 31-acre organic Northwood Farm, outside the village of Christow, west of Exeter. 'These are fixed price boxes, small, medium, large and large-shared costing pounds 4, pounds 5, pounds 6, pounds 7 respectively. We send out about 170 boxes a week to Christow and Exeter and there's a waiting list,' Mrs Deane says.

Last week's pounds 5 box included about 12 vegetables and one fruit - a melon, surprisingly. 'They take a lot of work, but the flavour is so much better than the ones you can buy in the supermarket' she says. Otherwise there were potatoes, carrots, spring onions, onions, leeks, spinach, green peppers, runner beans, cucumber, calabrese, cherry tomatoes and fennel. All of this is produced at Northwood either outdoors, or in polytunnels. In a year, she grows 50 different crops.

'There has been a big move towards direct marketing because people find they can get better vegetables that way. OAPs buy them because they think the vegetables taste good; families who are concerned about the environment and quality of food like it; students have twigged that it works out cheaper; and cooks like it because we supply herbs, such as coriander, in a huge bunch, not in the tiny, wilting packs you get from the supermarket,' Mrs Deane says.

She admits there is a problem in spring. 'We decided that instead of putting out boxes with the same six or eight vegetables each week, we would close down from the end of February until July. We were terrified our customers would desert us. But after three growing seasons, we have found this is not the case.'

What Jan Deane does for vegetables, Richard Young does for meat. He has been conveying his organic beef direct to the consumer since 1980. His motivation is animal welfare. 'We were rearing animals carefully to a set of tight welfare standards and we were always worried about how the animals were treated once they left us. When would they next be fed or watered? Might they be exported abroad?' he says.

He decided he would take on retail sales and control the whole business. 'We found a friendly butcher and he cut up the first animal on our kitchen table. Our first customer was the local doctor; then word got about and more people started buying it.' Now at their 470-acre Kite's Nest farm, outside Broadway on the edge of the Cotswolds, the Youngs have converted the basement rooms of the farmhouse into a butcher's shop and cold store. With two butchers and two more helpers, they sell the meat from their Welsh black and Lincoln red 70-strong beef herd, and some organic pigs.

Mr Young provides 400-500 people with meat that sells at a 10 per cent premium over conventional meat prices. The average spend is around pounds 80, with many customers stocking up their freezers on one trip. 'I think people like buying from us because they can see for themselves, at first hand, exactly how we rear our animals. Because we are organic, we never used the bought-in animal feed concentrates which are thought to have caused BSE ('Mad Cow Disease'). So we can say confidently that we will never have it on our farm.'

Northwood Vegetable Boxes (0647 52915).

Kite's Nest Farm (0386 853320).

A list of all the organic producers in Britain operating some form of Community Supported Agriculture is available, price pounds 1.50, from the Soil Association, 86 Colston Street, Bristol (0272 290661).

Also: Greenlink Organic Foods, Malvern (0684 576266) delivers down the M5 corridor to groups or individuals. A & R Veg Co-op, London (081-671 9944) runs a 'box' scheme with produce from Sunnyfields farm, Southampton. Old Plaw Hatch Farm, Sharpthorne, Sussex (0342 810857) runs a farm shop with dairy foods and vegetables produced by biodynamic methods. Bath Organic Buyers (0225 312116) delivers standard orders of organic produce. Wheelbarrow Foods, Barrow-on-Humber (0469 30721) is a group of growers that combines and delivers produce to groups. Goosemoorganics, Wetherby (0423 358887) runs a 'Vegebox' scheme. Ayrshire Organic Growers, Ayr (0292 570631) runs a 'subscription farm' producing fruit and vegetables. Harvest Moon Organic Produce, Insch, Aberdeenshire (0464 20388) delivers fruit, vegetables, dairy produce and cereals weekly to Aberdeen, Edinburgh and Glasgow areas. Goldhill Organic Farm, Blandford, Dorset (0258 860293) delivers fruit, vegetables and dairy produce. Organic Direct, Ledbury, Herefordshire (0531 631185) delivers produce from local organic farms along the M4 corridor.

Conference: 'Food, Farming and Society: Towards a New Model', 29 October, Regent's College, London NW1. Enquiries to the Soil Association (see above).

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