Conche, tempering and filling in chocolate production

The chocolate is stirred and heated in a conche tank up to around 90°C. The conche is a container with rotating knives (arms) that move in a circle and keep the chocolate mass in a liquid state through frictional heat. By stirring and heating the fat is released and homogeneously distributed, creating a soft, liquid-like flavoured mass. Due to the oxygen and the heat, moisture is removed from the mass, so that the moisture content in the chocolate drops to below 1%. Unwanted odours and aromas (e.g. acetaldehyde, acetone, butanol, ethanol, propanol, ethyl acetate, methanol, diacethyl) are discharged. The subsequent tempering or pre-crystallisation is carried out to achieve a beautiful surface, a firm break and further processing to optimise the required qualities of the chocolate. Tempering takes place in a container that cools the chocolate mass to below 29°C and then, depending on the type of chocolate, reheats it to 30°C or 32°C. Finally the chocolate is poured into its final shape, cooled and packaged.

For the instrumentation of these process steps, KROHNE offers perfectly suitable devices for temperature, level and flow measurement. For example, high-performance straight tube Coriolis flowmeters can precisely measure the mass flow of liquid chocolate. Fast, very precise OPTITEMP temperature sensors and continuous and non-contact OPTIWAVE FMCW radar level measuring devices with a flush hygienic lens antenna can also be used to monitor the temperature and tank contents.