Freshly mixed and refined chocolate mass is not yet where it should eventually be in terms of flavour and sensory quality. Only during conching does it develop much of its delicate aroma, smooth texture and balanced mouthfeel. To do this, the mass is moved, sheared, aerated and heated intensively over a longer period of time.
What happens during conching
Once cocoa mass, cocoa butter, sugar and – depending on the variety – milk ingredients have been mixed and refined, the chocolate mass is conched. Movement, heat and air work together over several hours.
- The surface of the fine sugar and cocoa particles is altered and evenly coated with fat.
- Moisture and unwanted volatile aromatic compounds, including excess acetic acid, can escape.
- The mass becomes more homogeneous and its flow behaviour changes.
- At the same time, the distribution of flavour compounds changes. As a result, the flavour profile can develop from sharp or tangy to rounder and more harmonious.
Conching is more than simply “stirring”: it is an interplay of mechanical processing, heat and aeration that influences the aroma, texture and flow behaviour of chocolate.
Time and temperature as important factors
When conching, it is not just the duration that matters. Temperature, mechanical stress and aeration also influence the result.
A longer conching time can further reduce unwanted volatile compounds and change the texture and aroma. At the same time, if the treatment is too intensive or too long, desirable flavour compounds can also be lost. That is why the process is tailored to the respective recipe and the desired flavour profile.
A dark chocolate with a high cocoa content is handled differently from a milk chocolate.
From fine melt to finished chocolate
The fine melt of chocolate is not created by a single processing step. Grinding first ensures that the sugar and cocoa particles are sufficiently fine. Conching then further develops aroma, texture and flow behaviour.
Only during subsequent tempering does the desired crystal structure of the cocoa butter form. It is crucial for typical characteristics such as gloss, a crisp snap and how the chocolate melts in the mouth.
This is how many individual processing steps create what we perceive when eating as fine melt and balanced aroma.
