Chocolate is made by roasting and grinding up cocoa beans to yield chocolate 'liquor'. This comprises around 50 per cent cocoa solids and 50 per cent cocoa butter (the fat from the beans). In the labelling of chocolate the cocoa solids generally include the cocoa butter - it's basically all the bits of the chocolate that are from the cocoa pod rather than the later additives such as sugar, milk, lecithin, vanilla, etc.
A huge range of eating and cooking chocolate is available in supermarkets and specialist shops, including chocolate made from organically grown ingredients and coming from Fairtrade sources. The difference between all the various brands depends on the type of cocoa beans used, the proportion of cocoa solids and cocoa butter, the sugar content and the flavourings. Producers of chocolate must meet certain minimum requirements before they can use the names prescribed by law for chocolate and its different types, such as milk chocolate. When buying chocolate, read the list of ingredients. Look at the percentage of cocoa solids and sugar, as this indicates the quality and taste of the chocolate. The higher the cocoa content, the less sugar it contains and the more 'chocolatey' it's going to be.
Seek out quality chocolate - the results will shine through. High-quality chocolate will make a distinctive, crisp, snap when broken, shattering cleanly. It should also start to melt when you hold it in your hand for a few seconds - the quicker the better, as this indicates a high cocoa butter content. (Cocoa butter has a melting point of 37C/99F, just below human body temperature, which is one of the factors that gives chocolate its enduring appeal.) In less expensive chocolate, vegetable oils and shortening have been substituted for the cocoa butter, and may even have been through the process of hydrogenation to lower these fats' melting point and reproduce cocoa butter's essential characteristic.
Legally, all chocolate can contain up to 5% vegetable fat and this must be one or more of the six types of vegetable fat specified by the European regulations.