Apart from Maltesers and the odd square of Swiss I’ve gone off milk chocolate in recent years. Even as a sugar-hungry child I found Mars bars sickly, and since adolescence I’ve rarely craved such a surge of soft, saccharine fat. But some people bear astonishing loyalty to specific brands. I often cook with Green and Black’s, despite the fact that like Cadbury’s it’s owned, apparently with some chafing, by a company that make aerosol cheese. Though Kraft has maintained Green and Black’s commitment to fair trade, its espousal of a movement set up in part to oppose it and other multinationals marks a tense and conflicted moment for fair trade – which had already been attracting criticism. Many ethically-minded consumers prefer to buy their chocolate from co-operatives like the Grenada Chocolate Company.