When roasted, cocoa develops its characteristic chocolate aroma. Important aroma precursors are already formed during fermentation and drying. Under the influence of heat, they are further transformed and supplemented by new aromatic compounds. Roasting therefore shapes the cocoa’s individual character.
What happens during roasting
Temperature and roasting time are tailored to the respective raw cocoa. Together, they form the so-called roasting profile. Depending on the cocoa and process, temperatures of around 125 °C are used, for example.
During roasting, numerous chemical changes take place at the same time. These include the Maillard reaction, which contributes to the typical roasted and chocolate aroma. Together with other browning reactions, it also changes the already brown colour of the fermented and dried cocoa.
At the same time, bitter and sour taste impressions can become milder depending on temperature and roasting time. The furry, astringent mouthfeel known as adstringency may also decrease. How these changes show up in flavour depends on the original cocoa and the chosen roast.
Preserving the delicate aromas of fine flavour cocoa
Fruity, floral or nutty notes arise from the interplay of genetics, origin, fermentation and drying. During roasting, the aim is to preserve this character while also developing the chocolate aroma.
As roasting time and temperature increase, strong roasted notes can overshadow the more delicate aromas. A shorter roast at a lower temperature can therefore be beneficial for fine flavour cocoa. What matters is a roasting profile that suits the characteristics of the cocoa in question.
Origin, post-harvest processing and roasting together help ensure that two single-origin chocolates with the same cocoa content can taste completely different. The percentage alone therefore gives only a limited picture of their flavour.
Why we roast cocoa nibs at Rausch
Cocoa can be roasted either as whole beans or in the form of cocoa nibs. In whole-bean roasting, the beans are broken open and separated from their shells only after roasting.
For our Rausch chocolates, we roast the cocoa nibs, the broken pieces of the dehulled bean kernel. This process allows the cocoa to be roasted particularly gently and evenly.
To do this, the whole cocoa beans are first gently warmed so that their shells come off more easily. The beans are then broken and the shells removed. Only then does the roasting of the cocoa nibs take place.
From cocoa nibs to cocoa mass
After roasting, the cocoa nibs are ground into cocoa mass. It forms the basis of our single-origin chocolates and carries the aroma profile that has developed from origin through to roasting.
The role conching plays in the further manufacturing process for aroma and melt is explained in the article Conching and melt.
