Solid chocolate

The researchers

Chocolate was brought to Europe from the American continent in the 16^th century and was originally consumed as a beverage. Filled chocolates, sugar-coated chocolates and chocolate confectionery were first produced in the 18^th century, but only on a small scale.

During the 19^th century, new techniques, introduced by the Industrial Revolution, replaced the laborious manual work of chocolatiers. Some major discoveries improved the quality of edible chocolate and its popularity rocketed. The Dutchman Casparus van Houten Sr. was the first to successfully separate cocoa butter from cocoa paste using a hydraulic press. This cocoa paste was pressed to produce what is known as a cake, then used to make cocoa powder. In 1847, in Great Britain, the Fry brothers, Joseph, Richard and Francis, discovered a way of producing a runny paste, which could be poured into a mould, thus making the first bar of chocolate. Their process involved adding cocoa butter to the cocoa powder, and sugar to refine the texture.

In Switzerland, Daniel Peter began to produce milk chocolate in 1875. As milk contains a lot of water, and cocoa powder has a lot of fat, it was difficult to obtain a stable emulsion from these two ingredients. The chocolatier therefore had the idea of using condensed milk, and reducing its water content even further. Some years later, milk chocolate arrived on the market. In 1879, another Swiss, Rodolphe Lindt, successfully developed a technique for refining chocolate, a process that later became known as conching. This gave chocolate its melt-in-the-mouth smoothness.

The changes chocolate undergoes

© Shutterstock / Pierre-Yves Babelon - Cocoa beans, the basic ingredient of chocolate

Firstly, cocoa beans are roasted to develop and release their aroma. They are then crushed to remove their husks, and pass through mills and grinding machines to emerge as cocoa paste. Part of this paste goes into large hydraulic presses in order to extract the cocoa butter.

Cocoa paste and cocoa butter form the basis of all chocolate, but the blend varies depending on the desired product. Plain or dark chocolate contains cocoa paste, sugar, and cocoa butter to ensure smoothness. To make milk chocolate, powdered milk or evaporated milk is added to this mixture. White chocolate, however, is made solely with cocoa butter, powdered milk, and sugar.

The selected mixture is churned and ground again to form a smooth, homogenous paste. At this stage, it is still bitter and grainy, so the next step, conching, is essential. Here, the paste is heated to a temperature of 80°C and then stirred for several hours. This reduces the bitterness and the chocolate becomes a perfectly even blend that melts in the mouth.
 

© Shutterstock / Deyan Georgiev - Pouring chocolate into moulds

The last stage, tempering, makes it easier to remove the chocolate from the mould. The mixture is again gently stirred, and heated to a temperature of 50°C, before being cooled to 28°C and finally, reheated to 31°C so that it has the right consistency to be poured into open moulds. After cooling, the chocolate is easy to remove from the mould and has a smooth, silky sheen.

An infinite choice

The three basic types of chocolate, dark, milk and white, come in an infinite number of varieties with countless additional ingredients, ranging from hazelnuts – which Peter Kohler was the first to add to chocolate in Lausanne (Switzerland) in 1830 and this has since become a classic – to more recent creations with salt or blueberries. Thanks to the imagination and expertise of chocolatiers, the creation of different shapes and types of chocolate, bars, truffles or pralines with a variety of fillings is endless!