In the course of time, chocolate processing has always been essentially the same, but thanks to technological developments, production has been optimized. For example, nowadays a more accurate control of the processing parameters is performed, in order to guarantee a higher quality standard. Moreover, every manual procedure has been eliminated, with the result of obtaining a highly hygienic quality.
Harvesting and fermentation
After the harvesting, cocoa beans are left to ferment by resting under banana leaves and twigs for a period between 2 to 6 days. The pulp, rich with sugars, drains away because of the fermentation, while the heat provoked by the process (temperatures may reach 50 C°) prevents the beans from blooming.
Beans are subsequently laid to dry under the sun's rays, usually on large mats or flat crates, and continuously mixed. In a week's time, most of the water has evaporated, and beans have turned brown, while their flavour has become stronger.
Once it has reached the production factories, rough cocoa undergoes a severe quality control. Specialized laboratory technicians make sure that the beans are healthy, that their fermentation has been correct and that they perfectly match the requirements.
Storage and cleaning
Beans that pass the quality tests are then stored in air-conditioned silos. Before the processing, rough cocoa is carefully cleaned with sieves and mechanical brushes. Wooden remains, sand and even the finest dusts are removed through extractor fans, while metal particles are retained by special magnets.
Grinding and decortication
Through a machinery called cocoa grinder, beans are chopped to medium-sized pieces - thus originating ground cocoa – then a system of sieves and extractor fans separates the beans' husk from ground cocoa.
It is necessary in order to release the cocoa beans' flavour. The roasting level depends on the use to be made of the cocoa beans: cocoa powder, for example, requires a strong flavour, while chocolate usually has a more delicate one.
Roasted and crushed beans are mixed according to different recipes: the dosage of cocoa varieties is among the chocolate producers' best kept secrets.
Typology of raw material
Three different typologies of raw material can be obtained from cocoa beans: cocoa paste, cocoa butter and cocoa powder.
- Cocoa paste – The mixture of ground cocoa beans undergoes a rough grinding, then a finer one. The heat originated by pressing and rubbing melts the cocoa butter in the seeds, thus originating the cocoa paste, a dense and dark liquid, which thickens through cooling.
- Cocoa butter – It's the fine fat contained in the cocoa seeds, obtained by the cocoa paste through big hydraulic presses. Filtered and purified, it looks like a thicker table butter.
- Cocoa butter is responsible for providing chocolate with some of its typical features – like its gloss and its “melts-in-the-mouth” softness.
- Cocoa powder – After the cocoa paste – from which the cocoa butter is extracted - has been pressed, the resulting material is the so-called “cocoa press cake”, which still contains from 10% to 20% fat. Through a further grinding and sieving process, the cocoa powder is obtained and, with the addition of sugar, the alkalized cocoa powder.
The preparation of veritable chocolate begins with the “mixing” stage. Starting with cocoa paste as base-ingredient, other ingredients are added – like cocoa butter, sugar and vanilla for dark chocolate; the same ingredients, plus milk or powdered milk for milk chocolate ; cocoa paste is not included into white chocolate's formula, which only consists of cocoa butter, sugar, vanilla, milk or powdered milk.
After mixing the basic ingredients, chocolate paste is finely ground, to give the sugar and cocoa particles a size compatible with the sensibility threshold of both the tongue's papilla and the palate. Then, in order to obtain a “creamy” chocolate, chocolate paste has to undergo conching: conching machines mix the mixture for a long time, at a controlled temperature. Soon afterwards, chocolate is put in large tanks (heated up at 50°C), ready to be transformed.
Before the final processing stage, chocolate has to undergo a very important treatment: tempering. During this phase, chocolate is gradually cooled down from 50°C to 27-28°C, while being continuously mixed, and subsequently heated up to 30-31 °C.
This process brings to the formation of small cocoa butter crystals – with peculiar properties – inside the chocolate mass. When chocolate is cooled down until it's completely solid, all the cocoa butter crystalizes in the same form originated by tempering. Therefore chocolate acquires important peculiarities – like that of being easily extractable from moulds, a velvety and homogeneous structure, a shiny aspect and a long preservation.
Moulds slide on a roll under dripping machines, which fill them with an exactly dosed quantity of paste, then pass on a pressure beating machine, whose vibrations eliminate air bubbles from the chocolate mass, and reach the cooling tunnel. Once they're cooled and solidified, finished products are extracted from the moulds and brought to the packaging sector – often a completely automated one.
3D shapes like Easter eggs or rabbits, Santa Claus etc. are created in plastic moulds, generally empty and openable in halves. The proper dose of liquid chocolate is poured into the moulds: then the moulds are closed and put into a centrifuge, in order to favour a correct distribution of chocolate on the inside.
Many modern products, like bars and some kinds of pralines, are produced by starting from a pre-formed “heart” (composed by gianduia paste, biscuit, wafer, hazelnuts etc.), which is coated in chocolate. Liquor pralines follow this proceeding, too: a pre-formed sugar shell is filled with liquor and then coated in chocolate. Ice creams like the cremini, some kinds of pralines and bars are made of sheets of chocolate or other ingredients one upon the other: once they're cool, they are cut into shapes and sizes of choice, and even coated in chocolate, before being packaged.
Chocolate packaging is a sector that has truly taken advantage of technological development. At the beginning of the twentieth century, chocolate tablets were hand-wrapped - first in tin foil and then in vividly coloured paper - then sealed with wax. Nowadays this is a fully automated process.