Dark materials: How to find the best chocolate, bar none

Premium chocolate used to mean a box of Black Magic. Now true connoisseurs are just as discriminating as wine buffs – but not all fine confectionary is equal.

Good news for chocoholics: there is more high-quality stuff around, it does not come from areas that exploit child labour, it has genuine health benefits, and you can now find a decent stash on nearly every high street in Britain.

But the bad news is it's not so easy to tellproperly made chocolate from over-roasted rubbish. "Belgian", "organic", "Fairtrade" and even "70 per cent" are mere marketing buzzwords – and not one of those designations is a guarantee of good taste.

"It's all about how well the beans have been cared for," says Paul A Young, a top chocolatier whose book, Adventures With Chocolate, which attempts to define quality as well as the special characteristics of cocoa beans grown in different countries, has just been voted best chocolate cookbook in the world.

"Chocolate from Madagascar, Venezuela and Ecuador all tastes different and can all be delicious," he explains. "But if the beans have been poorly treated – over-roasting them is one common form of abuse – the result will be bad chocolate. It's like wine – the grapes and soil don't tell the full story. The quality of the product is down to the wine-maker, and in chocolate it's all about how the beans have been cultivated and processed."

As an avid educator as well as truffle-maker, Young stocks dozens of varieties in his London stores, priced at a not-inconsiderable £3.50 for a little 50g slab to around £8.95 for tiny rare artisanal blocks by cult manufacturers Amano, Tcho and Mast of Brooklyn.

Despite the price, he has dozens of addicts who come in "every single day for a little piece of something". It may well be its addictive qualities that are driving the high end of the chocolate market. The dark stuff with a high proportion of cocoa solids promotes the release of serotonin and dopamine, the so-called "love drug", as well as theobromine, which gives the kind of kick associated with an espresso.

Paul and his many rivals – "there has to be a chocolatier in nearly every town in Britain now" – may be at the top end of a rarefied market, but they are having a huge impact on the high street. "We have had people from M&S in looking at what we are doing," he says, and Liz Jarman, technical developer of confectionery products for Sainsbury's, confirms: "We get chocolatiers in to give workshops to our buyers and help them understand what's involved in producing a really good bar of chocolate. There's been a lot of press coverage around premium chocolate, and while with the recession we're not seeing a huge rise above the £2 price point, it's an area of growth we want to invest in. We're spending a lot of time on what cocoa should go into our products from the point of view of where it comes from. We currently offer a couple of bars of single origin – Santo Domingo and São Tomé, for example – which have quite distinct flavours, and are looking at adding more."

Expect to see guidance for connoisseurs coming to a shelf near you soon: "We have adventurous customers who started trial-purchasing different coffees when we explained their characteristics, and we might do that for chocolate," adds Jarman, who also finds space for emerging small brands like Chocolate Society. Interestingly, that company distributes the wildly expensive Valrhona, one of the finest sources of chocolate "couverture" (the blocks used by chefs and chocolatiers as their raw material), yet Jarman admits Sainsbury's, the first supermarket to make Valrhona available to British foodies, could not sustain the price for the French bars, which is double or treble the price of Menier and Green & Black's that dominate the home-baking shelves, along with their own brands.

However, Valrhona, which processes the finest beans gathered from all over the world in its factory on the Rhône, has been snapped up by Waitrose, which, unlike its rival supermarket, has seen a staggering 60 per cent annual rise in the value of cooking-chocolate sales. "There's been a surge in home baking with the recession, chefs are talking up good-quality ingredients, and we are able to trade customers up like no other retailer," says Chris Moore, buyer of cooking chocolate for the chain, which has just retained Heston Blumenthal as its spokesman.

Today, modest £1 bars of Menier still sit alongside £5 bars of Valrhona on Waitrose shelves, but they have been joined by much more esoteric products – like the chocolate fondue in a barbecue pack from Mortimer. Moore says the chain has been successful with tiny, costly cylinders of 100 per cent cocoa solids from Willie Harcourt-Cooze, one of the few small producers in the world to undertake the arduous task of making his own chocolate from the bean. You wouldn't want to eat this – many people find even 70 per cent chocolate insufficiently sweet – but Moore says: "People are now using chocolate for savoury purposes as well as sweet. They grate it into chilli con carne or to make a richer gravy."

Young makes a Marmite truffle, and his cookbook includes intriguing savoury recipes using sweet chocolate, including a chocolate, Stilton and bacon sandwich and a chocolate-enriched sauce for chicken which is a take on mole, the chocolate sauce beloved of the Mexicans, who were cooking up chocolate with chilli several hundred years ago. It was a grim brew, by all accounts; only after the conquistadores brought the strange substance back from the New World did the Swiss set about adding milk and sugar to make a palatable new confection. Today, it's back to unsweetened chocolate for drinking and in unlikely formats, sometimes: Teapig's chocolate-flake tea, available from Harvey Nichols, is a best-seller.

Today, chocolate is grown throughout the tropics, mostly in West Africa, where controversy is brewing. Marc Demarquette, Fortnum's house chocolatier, is concerned about child slave labour and last year pulled Ghanaian chocolate out of the signature collection he makes for his London boutique. Demarquette was a management consultant until a moment of epiphany sent him to Paris to train as a chocolatier.

Demarquette was retained by the team who made last night's Panorama programme to explain how chocolate is converted from bean to bar. He says: "The Ivory Coast is also suspect. And I have never used chocolate from there." Divine, the big name in Fairtrade chocolate, is 45 per cent owned by Ghanaian farmers, but insists its practices are ethical.

Fairtrade is a buzzword that has helped grow the premium chocolate market, though neither Demarquette nor Young believes it is synonymous with good taste any more than the "organic" designation that has given Green & Black's a massive share of the premium chocolate market. Gerry Wilton, who runs truffle-making workshops all over England including at his Chocolate Boutique Hotel in Bournemouth, calls Green & Black's: "the best of the worst", and Young says: "I would agree with that, although I would buy that or Menier for home baking if I couldn't get any Valrhona."

Perhaps the best evidence of Britain's growing love affair with good chocolate is the transformation of Thorntons over the past two years. "It's not about trading up, because we still have a broad customer base, but we've been anxious to improve the quality of what we offer," says marketing director Peter Wright. Its current chocolatier, Keith Hurdman, has developed many new flavours for the 600-strong chain, and has refined what it offers to the point where it now fields 24 bars, many of single countries of origin, which have won Taste Awards or the chocolatiers' equivalent of Oscars from the Chocolate Academy. "There's a definite shift towards better quality and a move towards darker," says Wright. "And we consider our growth of 5.5 per cent over the past year pretty good in a recession."

He is only frustrated not to be able to introduce Thorntons' new planned Limited Edition bar of Colombian chocolate infused with coffee, because the raw material comes from a very small supplier and is trapped in customs limbo. So the Madagascar with salted pistachios may get a longer life than originally intended.

It's all a long way from Milk Tray and Black Magic – but there will always be a place for our home-grown favourites, more than a few of which could not even be marketed as chocolate in Europe until recently because of their low proportion of cocoa solids. Young confesses: "I was eating some Cadbury Creme Eggs last night, and they just took me back to my childhood. They're soul food, they're about memories – they're just not good chocolate. But what you think is good chocolate comes down to personal taste. It's much easier to define bad – it tastes bitter or flat and might even give you a hangover. Good chocolate sparkles in your mouth and makes you want more – though you may be surprised how satisfied you can feel after just a couple of squares."

Adventures with Chocolate is published by Kyle Cathie, £17.99

Hot chocolate: Where to buy it

Top brands used by professionals include Valrhona and Amadei. High street supplies of these are limited (though Waitrose stocks some Valrhona) but Thorntons has improved the quality and variety of what it offers while maintaining low prices.

Visit specialist chocolatiers in person or via mail order to discover your personal taste preferences. The following selection is just a sampling.

Willie Harcourt-Cooze – Bars, cooking cylinders and pure cacao of different origins from the only Brit making and marketing his own chocolate from the bean. Willieschocolateshop.com

Paul A Young – Truffles, own-brand bars, rare artisanal brands, tasting events at London shops. Paulayoung.co.uk

Hotel Chocolat – Bars, chocolates, gifts, and monthly mail order tasting club. Hotelchocolat.co.uk

T'a Chocolate – Many fine single-origin bars and flavoured chocs which have just launched in Selfridges

Terre a Terre – Delicious salted caramel or rum truffles which make bog-standard Belgian dark chocolate taste superb. Terreaterre.co.uk

Better bar – And the award for the best bar goes to Marc Demarquette, for his dark chocolate flavoured with vanilla salt. Absolutely to die for. Demarquette.com