At the nibbing stage, the different beans are blended to create cuveés. A cuveé is the term used to describe what happens when wine makers blend two or more grape varieties, which have been chosen for their complementary characteristics. The process is used particularly when blending a champagne and is similar to the art of the parfumier in creating a perfume. A notable specialist chocolate producer is Valrhona, based in the Rhone Valley, in France. There they take a special pride in the art of fine chocolate making. Their attention to detail is uncompromising, and they have a panel of twelve chocolate experts who meet every day and taste the different ‘Grand Cru’ chocolates to ensure their consistency and quality.
Unlike wines, which vary according to the year in which they were harvested, cocoa beans do not normally suffer from weather fluctuations. The period of time which elapses between the harvesting of the raw cocoa and the manufacture of a bar of chocolate is usually a matter of weeks rather than months, but dried cocoa beans can be stored for a long time in a controlled environment; and careful blending ensures that each vat of the world’s finest chocolate has a predictable flavour, texture and aroma.
After the cocoa butter has been pressed from the cocoa mass, there is a parting of the ways: the industrial manufacturers separate the two parts, for cocoa butter commands a high price on the open market, being much sought after by the pharmaceutical and cosmetics industries. It is a unique fat because it is solid at 33°C (91.4°F), but melts at 34°C (93.2°F) just below blood temperature 37°C (98.6°F) which makes it ideal as a base for lipstick, among other things. This century has seen the invention of a number of cocoa butter substitutes, or ‘enhancers’ as they are also called in the trade. They are used to replace cocoa butter in the manufacturing of chocolate. Personally, whatever reasons the industrial manufacturers give to justify the process on commercial grounds, I do not believe that there is a satisfactory substitute for pure unadulterated cocoa butter. Nevertheless, it is common practice to sell off at least part of the cocoa butter and replace it with different sorts of ‘butter’ fat, derived from various nut and palm oils.
The other important difference between mass-produced chocolate and artisan chocolate is the addition of artificial vanilla, known as vanillin. Some would say that it is indistinguishable from the real McCoy, and perhaps if it were used with a little subtlety, it might be hard to tell the difference, but in my experience it is usually obvious just from the aroma of the chocolate. The tradition of adding vanilla to chocolate goes back to Cortés, and many chocolate makers believe that our palates are now so accustomed to that flavour that chocolate would taste very strange without it. The smaller specialist producers, on the other hand, still prefer to mix the cocoa mass and cocoa butter back together, adding a little sugar, powdered or condensed milk (if it is to be milk chocolate), and pure vanilla. It was Henri Nestlé and Daniel Peter, at Vevey in Switzerland, who perfected the technique of using evaporated milk, so that it could be incorporated into solid chocolate. The mixture is then further ground to a particle size of 18-20 microns, which is indiscernible to the palate.
The next stage is where the conching takes place. The conching machine was invented in 1880 by another Swiss pioneer, Rodolfe Lindt. The name derives from the shape of his prototype, which was a large, shell-shaped vessel. It works by grinding the chocolate between granite rollers to create a very smooth, velvety texture. The effect of conching is to refine the chocolate and remove any residual bitterness. Before the invention of conching, eating chocolate would have been very rough and gritty in the mouth, and would not have had the sensual qualities of present-day fine chocolate.
Conching is a process which ought not be hurried, yet for the cheaper chocolate bars this stage is often cut down to the minimum time, that is about twelve hours. Other producers allow conching to continue for up to seven days, adding extra cocoa butter in order to make the finished chocolate even smoother, and to give it greater fluidity. This is an important factor when it is to be used for dipping chocolate, making bonbons, truffles, mousses and so on. The name of this quality of chocolate is ‘couverture’, from the French word meaning covering. In translation the word brings to mind all the worst sorts of chocolate cake coverings which in some cases contain no real chocolate at all; just fats, sugar and flavouring. By contrast the French term ‘couverture’ is a very precise one: it means a chocolate with at least 32 per cent cocoa butter. Any chocolate bar meeting this specification will not only be good to cook with, but will also make excellent eating.