Banks and hedge funds in London are coming under increasing scrutiny over their practice of speculating on food prices.<br /><br />The allegation is that financial institutions are buying up vast stocks of food, thereby forcing prices to rise. <br /><br />This comes as food costs are increasing the world over. And as the revolt in Tunisia and other countries has shown, there is a social price to pay for this kind of rise. <br /><br />Al Jazeera's Laurence Lee reports.
