Corn-fed animals are fuelling America
Biofuel demand is not the only market pressure being felt by US corn farmers. Much of the fast food that powers Americans – a $100 billion annual market – is indirectly made from corn
as well, according to researchers in Hawaii.
Hope Jahren and Rebecca Kraft of the University of Hawaii purchased 486 servings of hamburgers, fries and chicken sandwiches from McDonald’s, Burger King and Wendy’s in Los Angeles, San
Francisco, Denver, Detroit, Boston and Baltimore.
Back in the lab, they analysed the carbon isotope content of each serving. Previous research has shown that it is possible to determine whether an animal ate predominantly corn feed or
grass from the ratio of C13 to C12 in its body tissue.
The pair found that 100% of the chicken in these three fast-food chains had been reared on corn alone. Some 93% of the beef came from cows that had been fed a corn-only diet. Just 12
burgers – all from west-coast Burger Kings – came from beef that had eaten something else.
The team was even able to determine what type of oil the fries had been cooked in – a mixture of vegetable oils at McDonald’s and Burger King, corn oil at Wendy’s. In fact, of 160
products purchased at Wendy’s, the researchers did not find a single one without some corn component.
«The trend over the past few decades has been to push for cheap animal protein», says Vicki Hird of environmental campaign group Friends of the Earth. She notes that
government subsidies that favour corn have encouraged pesticide- and fertiliser-intensive monoculture farming in the US. «We are using corn in ways that are completely
unsustainable», says Hird.
Friends of the Earth is compiling a report on the effects of intensive farming on the demand for soy, and the environmental consequences for South America. The growth of soy farming in
countries such as Brazil has driven deforestation and the destruction of grasslands. Much of the soy, says Hird, is used to feed cattle and chickens around the world.
Hird warns that the US and European push for corn-based biofuels could mean that intensive cattle and chicken farmers in the US will also turn to soy-based feeds.