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Who’s afraid of trans fats?

In “Fear of Frying,” David Schleifer gives us, in the words of his subtitle, “a brief history of trans fats,” and it’s a fascinating read. Trans fats are partially hydrogenated oils: attaching more hydrogen atoms to the oily backbone turns liquids into solids. First introduced at the turn of the century, they were all the rage by the 1960s because they were easier to use (e.g., in deep frying) and didn’t go rancid quite as quickly, but also because of (never fully substantiated) hype about how bad saturated fats were for you.

Some fifteen years ago, however, studies started to associate them with heart disease, diabetes and infertility. They have recently been banned from New York City restaurants. But unlike big tobacco, big food didn’t “deny the good science, buy some bad science, and try to avoid regulation.” What they did – despite the difficulties and costs involved – is jump on alternatives to trans fats, even before consumers started to change their minds in large numbers. In effect, they fostered perceptions of risk to drum up demand for a product that addressed that risk: value adding and niche marketing through fear. What’s the next big thing? Omega-3s fats, essential nutritionally but destroyed by hydrogenation. But it probably won’t be long before something bad is found out about them too and we all get onto the next bandwagon.

All very scary, but how is this relevant to the subject matter of this blog? Well, each of these shifts in consumer demand required new technologies, including new crop varieties. So, for example, the National Sunflower Association and the United Soybean Board, among others, developed cultivars whose oil does not need partial hydrogenation. But these are liquid, and difficult to use in baked goods, so palm oil is increasingly used, apparently. And Monsanto is projecting unveiling an enhanced omega-3 soybean by 2012.

Ok, so that’s one way to look at the role of agricultural diversity. Another is that you should stay away from processed foods and try to base your diet on a diversity of fresh ingredients, traditionally prepared. Which, by sheer coincidence, is the subject – or one of them – of a Time magazine piece this week on “How the World Eats.”

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Climate change and agriculture

A press release from the Smithsonian Institute draws attention to a study that links climate change, culture and agriculture. Mexico’s Central Balsas Valley is believed to be one of the sites where farmers domesticated maize and squashes. The new data suggest that the climate in the valley became cooler and drier at the end of the most recent ice age. Lakes in the valley formed at around that time and became magnets for human settlements, which contain evidence of maize and squash pollen. Of course, we’re not saying that climate change is always a good thing …

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Pollo y kumara

Chickens crossed to South America from Polynesia, while sweet potatoes went the other way, who knows, maybe in the same canoes. Ok, let’s unpack that a little bit. A DNA study has found links between 14th century (i.e. pre-Columbian) chicken bones buried on the coast of south central Chile and chicken bones from Polynesian archaeological sites, particularly on Tonga and American Samoa. Meanwhile, ocean circulation models suggest that, contrary to previous thinking, a ship setting off from various points along the western coast of South America could indeed have delivered sweet potato seed pods (and bottle gourds?) to Polynesia (in particular the Marquesas) in a relatively short period. These studies have been all over the news lately and are being much discussed in the blogosphere. For example, Gene Expression and John Hawks work through some of the anthropological questions.

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Marginality and animal genetic resources

The conventional wisdom is that landraces and local breeds are better adapted to marginal conditions than modern crop varieties and livestock breeds. A paper has just been published in Agricultural Systems that tries to quantify this. The researchers defined marginal areas “as those areas where possible land uses are relatively limited because of higher altitude, shorter growing season, steeper slopes, less fertile soils or broadly speaking because of generally lower soil productivity.” They calculated a synthetic index of marginality using all kinds of environmental and socio-economic data and mapped its value throughout Europe. They also mapped the distribution of goat and sheep breeds using data from the Econogene project. Then they calculated how good the marginality index was at predicting the presence of local breeds. The result: “Increasing marginality, as measured by these indices, is positively and significantly correlated to the fact that local, traditional breeds are present.”

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Re-wilding Europe

There was much talk a couple of years back about re-wilding – a suggestion to establish a plausible facsimile of the Pleistocene fauna of North America by introducing carnivore and herbivore species (including wild relatives of livestock) from Africa and elsewhere to the Great Plains. ((Check out a recent interview with a proponent. There’s even a Rewilding Institute now.)) But perhaps Europe might be a better candidate for this kind of thing.