I plead guilty. I was in Tesco. It was a perfectly ordinary shopping outing, looking for food for the week, and maybe there would be a wee bottle of something on the trolley as well, as a treat.

What has been churning in my mind since then, more than usual, has been the source of the food that I was looking at, and considering buying. There were beans from Thailand competing with beans from Kenya. Or if you really spoiled yourself, you could have a mixed packet of beans and baby sweetcorn from “Kenya and Peru”.

I happen to know Kenya quite well. I have lived and worked there, and my views about the Kenyan beans are quite complex and confused. That country is short of food, but not in the areas where the beans are grown. Meanwhile someone with a little land is earning an income that they would not otherwise have by growing the beans. And yet it must be crazy to fly beans 5,000 miles. All those carbon emissions.

I then carry on past the meat shelves. New Zealand lamb. In Shetland. You’ve got to be joking. How can it make sense to cart the poor beast halfway round the world to an island that oozes sheep from every pore? At this point, I was minded to put back on the shelf the Spanish tomatoes that I’d put in my trolley, even though they had only come about 1,500 miles.

So I got home with a whole load of stuff that I probably didn’t want, certainly didn’t need, and which was giving me a bad conscience. I opened the bottle first, which had come all the way from Chile, and then I got Googling. You can do it too, but I’ll tell you some of the things I discovered or worked out and you can see if you share some of my puzzles and conclusions.

The average distance that any given kilogram of food travels, from its source to your kitchen, is between 1,500 and 2,000 miles. So that makes my Spanish tomatoes very ordinary. I have no idea how anyone works something like this out, but apparently that average distance is about 25 per cent more than it was in 1980. What is clear is that we have got used to collecting our food very widely. Food is distributed through a global market, promoted by the globalisation of finance and trade, and by refrigeration and other food technologies.

Transport accounts for 12 per cent of the carbon gas emissions associated with food. Globally, that is a huge amount of gas, but perhaps not as high a proportion as you might have thought. Believe it or not, farm animals give out more greenhouse gases than that, and the most serious carbon emissions come from factors such as the manufacture of fertilisers and all the plastic used in packaging.

You also have to think a little bit laterally. If a 40-ton lorry drives fruit from Spain for delivery at a group of supermarkets, less fuel will have been involved than if hundreds of families drive a few miles each way to pick-your-own fruit farms. Not that we have too many of them in Shetland. And as for my tomatoes, less fuel is involved in bringing them from Spain than is needed to heat greenhouses when tomatoes are grown in Scotland. For good measure, the lorry that brought the tomatoes can go back to Spain with Shetland shellfish that give us profitable jobs and keep the Spanish and all their tourist visitors in paella.

But surely we can’t talk ourselves into excusing the New Zealand lamb? Well maybe, actually. A study by Lincoln University in Christchurch, New Zealand, calculated that New Zealand lamb, delivered in Britain, involved fewer carbon emissions than the equivalent British product. The main reasons given for this are that almost no fertiliser input is involved on New Zealand pasture, and no winter feeding is involved there.

It is, I suppose, all about money. A given product of a given quality appears on the shelves from the cheapest possible source. More important to the price than the cost of the transport are the costs of production and processing. Scale of production keeps costs down, and so do the geographical and social circumstances in which food is produced. Spanish tomatoes don’t need heating. Brazilian cattle thrive on ground hacked virtually for free out of the rainforest, where they are tended in huge numbers by cowboys who are paid a fraction of what they would be in Europe or North America. Agriculture in each different environment of the world has become more and more specialised.

This global food market in its present form depends on the availability of relatively cheap oil. That is changing, and will change a great deal more. I am old enough to remember that the first gallon of petrol I ever bought, in 1962, was eleven bob – 55p a gallon, or 12p a litre, to you younger ones. Even today, at nearly £7 a gallon in Shetland, petrol is not much more than bottled water.

That cannot last, as the real price of fuel will surely rise continually from here on. The proportion of food costs spent on transport will rise from the present 12 per cent, and food production costs will rocket as fertilisers, tractor fuel, packaging and everything else all go up. Then it will make more economic as well as environmental sense to cut the “food miles” and eat locally produced food.

Here in Shetland that means that we should set our minds to things that we can perhaps produce, or produce again, that would cut our food miles. Maybe we should be trying to get enough of that wind-driven electricity free so that we can economically grow our tomatoes and bananas here, in heated glass-houses. The Icelanders grow good tropical fruit over their natural hot springs. Or perhaps we should be developing hydroponics – growing vegetables under cover without soil, with the roots in treated moving water.

Can anyone over about 60 remember the first frozen peas they met? It was probably some time in the late 50s, as the first frozen peas ever were sold in 1952. (And that’s the kind of fact that Google really helps you to come up with!) Before that, we all ate food much more in line with the seasons. We have come to expect to be able to buy the food that we want to buy at any time of year. Kenya, Peru, Spain. It will be summer somewhere. Iceberg lettuce can be supplied to supermarkets 12 months a year by companies that have farms in five continents.

But we all associate Brussels sprouts with Christmas dinner for a good reason. Before freezing, sprouts were the only green vegetable likely to be available in Scotland in December. That is the kind of thinking that perhaps we should get back to. Eat seasonal food, prepare more of it at home, and use gulls’ eggs for baking while we’re at it.

One last thought. Cuba is an interesting place. Somehow, Castro is a more interesting character than your average dictator. One feature of Cuba is that they have almost permanently been short of oil, though nowadays Venezuela is helping them out. The shortages have stemmed from the American boycott of the island, and the Cubans have adapted to the situation. They run what may well be the world’s first “post-oil” modernised agricultural economy. The Communist state in the 90s gave up its attempt to manage all farming. Food is produced very locally, by small producers who work and market their produce privately, using animal power and the sweat of their own brow. Industrial crops, which in Cuba means sugar, with some tobacco and cotton, are produced on big state and co-operative farms. Fuel for this is paid for directly by the exports generated. Meanwhile, the country is learning to live providing its own food sustainably, without oil dependence. They are still dependent on food imports, particularly of rice, but things are apparently improving. What would be the equivalent development here?

Danus Skene


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