As soaring commodity prices spark food riots around the globe, prompting a U.N. official to dub the production of biofuels at the expense of food cultivation "a crime against humanity," the debate over the efficiency and morality of using plants as an energy source is heating up. And Brazil, the world's largest producer of biofuels and leader in cheap and efficient production of ethanol, is fighting back against what it calls "disinformation and dishonesty."

A number of recent studies have suggested that ethanol production does more harm than good to the environment, and is at least partly responsible for the sharp jump in global food prices. And U.N. ... Read full article