- Completely copied pasted from fragglerocker's post.
Chocolate is a product made from cocoa beans and other ingredients. It was only made possible by industrial manufacturing technology. The drink made from cocoa beans and water by the Aztecs and introduced to Europe after the Spanish occupation was a primitive concoction that might be derisively called cocoa bean soup, but which nonetheless had enough flavor, theobroma and caffeine to inspire tireless experiments into its refining and concentration.
Today the word "chocolate" has two meanings. In the consumer market it refers to any confection whose most important ingredient is some part of the cocoa bean, usually those that are edible (and therefore contain a healthy dose of sugar) but also including baking chocolate.
But to a chocolatier (a person who makes the aforementioned confections) and for the purposes of this discussion, as defined by the introductory question, "chocolate" is the raw material the chocolatier works with. This is an industrially manufactured substance "whose most important ingredient is some part of the cocoa bean." The cocoa beans are pulverized and heated and the cocoa butter and cocoa solids are refined out of them. The cocoa butter and cocoa solids are then blended in a specific proportion and combined with sugar. An emulsifier, usually lecithin, is also used. Milk is added to make "milk chocolate." The factories whose products are regarded as reference standards stop there, but other flavorings can be added.
The route of cocoa beans was the opposite of coffee beans: they originated in the Americas and were introduced to Africa, and are now grown commercially in many regions. But like coffee beans they come in many varieties, each with its own subtle difference in composition that can make a profound difference in flavor.
The "chocolate" produced by these factories in bricks weighing several kilos is edible straight off of the assembly line and is what you get if you buy a "plain" chocolate bar. The difference from one to another is primarily a matter of two vectors.
One is the choice of beans. Like coffee beans, tea leaves, wine grapes, or any other foodstuff whose primary purpose is not nutritional, remarkable differences in flavor occur in various types or mixtures and each has its own devotees.
The other is the percentage of cocoa in the mix. The more cocoa, the "darker" or more "bittersweet" the chocolate. Generally the product must be at least 50% cocoa to be called dark or bittersweet, but purists sniff at anything much below 70%. Milk chocolate is so low that the percentage is not listed.
Varying the proportion of cocoa butter to cocoa solids will also have an impact on the results, but I have never encountered any information on this part of the process.
White chocolate is a special case, it has only cocoa butter with no cocoa solids and therefore lacks caffeine as well as the typical chocolate color, and tastes "like chocolate" but not "like chocolate." It has a higher melting point than cocoa solids and makes a good summer candy.
In Soviet Russia, chocolate taste like YOU!!