Nobel Prize-winning economist Gary Becker assigns great blame to ethanol subsidies for the food shortage that UN Secretary-General Ban Ki-moon says "has reached emergency proportions." The ethanol lobby is yelling its head off trying to separate ethanol welfare from food inflation. I think I'll believe Gary Becker:

Rather, the boom in petroleum prices and subsidies to ethanol and other biofuels are the most important forces explaining the recent increase in food prices. Both the sharp run up in oil prices, and the continuing subsides to ethanol production in the United States, and to a lesser extent Europe, induced an increasing diversion of corn from feed and human consumption to the production of biofuels. The main goal of the diversion has been to produce more ethanol as a substitute for gasoline. During the past year, one quarter of American corn production, and 11 percent of global production, was devoted to biofuels, and the US contributes a lot to the world corn market. The growth in demand for biofuels explains why acreage was shifted from other grains to corn-the acreage devoted to corn in the United States increased by over twenty percent in 2007-8, while that devoted to soybean production declined by more than fifteen percent. The reallocation of production away from other grains explains the rapid price increases for wheat, soybeans, and rice as well as for corn.