The head of the world's largest food producer believes high prices are due to the growing of crops for biofuels."The time of cheap food prices is over," says Nestle chairman Peter Brabeck-Letmathe. He is highly critical of the rise in the production of bio-diesel, saying this puts pressure on food supplies by using land and water that would otherwise be used to grow crops for human or animal consumption."If no food was used for fuel, the prices would come down again - that is very clear," he says. "We are now in a new world with a completely different level...