1. The Cocoa Beans are Transformed After arriving in Switzerland, the imported raw cocoa is subject to a strict quality control. Laboratory technicians ensure that the cocoa beans are healthy, perfectly fermented and dried and have suffered no damage during transport. If the result of the test is satisfactory, the raw cocoa particularly in larger chocolate factories first stored before undergoing further processing. This is generally carried out in silos which measure from 40 to 120 feet in height and have a capacity of up to 1000 tons or more. The raw cocoa is sucked up by powerful vacuum extractors and carefully fed into the silos from above. This process also includes pre-cleaning treatment. Only the most careful treatment of cocoa in store will ensure that the quality does not deteriorate. Air temperature and humidity are therefore rigorously controlled and constant ventilation assured.
Cleaning Before the real processing begins, the raw cocoa is thoroughly cleaned by passing through sieves, and by brushing. Finally, the last vestiges of wood, jute fibres, sand and even the finest dust are extracted by powerful vacuum equipment.
Roasting The subsequent roasting process is primarily designed to develop the aroma. It bas long been known that certain foodstuffs not only become more wholesome but also acquire an improved aroma as a result of roasting we need only think of coffee, almonds and hazelnuts. Depending on the purpose for which they are intended, the beans are more or less intensively roasted; for cocoa powder, for example, a strong aroma is desirable whereas for chocolate, especially if it is of high quality, a subtler aroma is preferable. The entire roasting process, during which the air in the nearly 10 feet high furnaces reaches a temperature of 1300C, is carried out automatically on a conveyor system within a period of 15 - 20 minutes. In the meantime the cocoa beans have become quite dark and their flavour a little milder. A side-effect of roasting is the loosening of the husk from the cocoa bean. As the outer skin is heated to a higher temperature than the inside of the seed, it becomes brittle, separates slightly from the seed, and can thus be more easily removed during the subsequent crushing process.
Crushing and shelling The roasted beans are now broken into medium sized pieces in the crushing machine. Thereupon a system of sifting and air currents removes the husks from those parts which will be used to make chocolate. The separated cocoa bean husks are passed on to the chemical industry which is still able to extract valuable ingredients from them.
Blending Before grinding, the crushed beans are weighed and blended according to special recipes. The secret of every chocolate factory lies in the special mixing ratios which it has developed for different types of cocoa. As we have already mentioned, the producing countries supply various kinds of raw cocoa which differ widely not only in quality but also in taste. It is precisely the skilful blending of these individual aromas which determines — especially as far as plain chocolate is concerned — whether a particular chocolate has a delicate, a strong, or some other specific flavour.
Grinding The crushed cocoa beans, which are still fairly coarse are now pre-ground by special milling equipment and then fed on to rollers where they are ground into a fine paste. The heat generated by the resulting pressure and friction causes the cocoa butter (approximately 5000 of the bean) contained in the beans to melt, producing a thick, liquid mixture. This is dark brown in colour with a characteristic, strong odour. During cooling it gradually sets: this is the cocoa paste.
Source : Chocologie published by Chocosuisse CH-3000 Bern