Business Green: Pressure is expected to mount on retailers and food manufacturers selling products containing palm oil from plantations that contribute to rainforest deforestation, after Unilever yesterday announced plans to only use palm oil that has been certified as environmentally sustainable. The multinational giant said it is to work with industry group the Roundtable on Sustainable Palm Oil (RSPO) to begin sourcing palm oil that has been certified as meeting its new sustainability criteria. …