Chocolate Manufacture

There are three main products from cocoa, cocoa powder, plain chocolate and milk chocolate. The steps involved are more or less the same for milk and plain chocolate, with the obvious exception of adding milk. However the first few stages are the same for both cocoa powder and chocolate. Fermentation and drying, and often roasting are usually performed in the country where the cocoa was grown, apart from being much easier, this also ensures that no live seeds leave the country, as many cocoa producing countries are rather poor, and depend heavilly on cocoa.

Common Stages.

Fermentation
Beans removed from the pods are left to ferment for 5-6 days. This is usually at a raised temperature (45-50°C). The seeds germinate and die.

Drying
For 1-2 weeks the beans are left on mats or trays in the sun to dry, during this process they loose approximately half their weight, while the enzyme action from the fermentation continues.

Roasting
The beans are roasted for 1-2 hours at 99-104°C for chocolate or 116-121°C for cocoa powder. This process helps to develop the flavour and aroma.

Winnowing
The beans have their shells removed by a cracking and fanning process, producing "cocoa nibs".

Dutching (alkalizing)
This process was invented by the Dutchman Van Houten, cocoa nibs are heated with potassium or sodium carbonates before the grindng process to improve the misability (not solubility) of the resulting cocoa. This process also weakens the flavour and darkens the drink, and is not used by all manufactures.

Grinding The nibs are then ground to produce waht is known as chocolate liquor. It is here that the paths for cocoa powder and chocolate split.

Cocoa

Dutching
This step is more or less required to make cocoa properly, but is identical to the Dutching step above.

Pressing
The Chocolate is pressed to remove the fat. This was originally done by boiling and skimming, but Van Houten (see Dutching) produced a hydraulic press, which was far more efficient. After the grinding process there is approximately 53% cocoa butter, this is reduced to 27% by pressing.
The cocoa cake and cocoa butter are used in the production of chocolate, although cocoa butter is only likely to find it's way into expensive quality chocolate.

Pulverising
The cocoa "cake" is then pulverised to produce a very fine powder, this is then sifted to produce cocoa powder.

Chocolate

Mixing
The ingredients are mixed. These will include cocoa cake and sugar, and may also include cocoa butter, milk, vegetable fats and flavourings. The chocolate ingredients are places in a melangeur, which works rather like the conching machine below. This is used to ensure that the ingredients are correctly mixed together, and help to start making the chocolate smooth. This process also improves the flavour.

Conching
This process can take several days, but is essential for smooth eating chocolate. The ingredients are kept warm, and have heavy rollers passed over a curved bed, the chocolate is "crushed" and then slops over the side of the bed. This helps to improve the flavour, and is critical for quality dark chocolate.

Tempering
This process stops the cocoa butter crystalising out of the chocolate, giving a blotchy, granular appearance. The chocolate mix is heated and then carefully cooled to create the required crystal structure.

Moulding
The chocolate is now ready to be used, and can be moulded into the appropriate shape, or used for coating.