A conche is a machine in which liquid chocolate is mixed, grinded, agitated, and aerated. It is comprised of a container filled with grinding materials, such as metal beads. These ground the chocolate particles down to sizes small enough that they can’t be felt in the mouth. Heat generated by friction in the machine keeps the chocolate in liquid form throughout the process, which can last for up to 72 hours for high-grade chocolate.
Conching can last for as little as four to six hours. The liquid chocolate is then stored in tanks at temperatures up to 122°F (about 50°C) until it undergoes the final processing steps. The chocolate achieves its desired level of smoothness in the conche. Particles are ground up and coated with cocoa butter and an emulsifier, while water vapor and other undesirable substances evaporate. The length and nature of the process can create flavor, but flavorings can also be added into the chocolate conche machine to give the product its taste.
Various cooking techniques are used, depending on the conche. Some machines have a roller-style format that is configured into long troughs. Other systems are circular, a design that is more commonly utilized to make chocolate. Conching machines come in various styles and many offer low-maintenance, optimal heat transfer, and high-strength seals to ensure a cost-effective means of production. A compromise of the most force and power versus a low risk of overheating chocolate is also preferred.
Methods of conching include both a standard and rapid process method. Rapid conching machines operate at higher speeds and can cut up to 20 minutes off the processing time, which is suitable for white chocolate or if the chocolate mass is being filled with extras, such as nuts. Continuous conching can be performed without adding substantial flavor or for refining a dry powdered milk and cocoa mixture into a liquid. Conche machines may also have automated features, such as speed controls for motors.
The length and speed of the mixing depends on the type of chocolate that is being made. A conche can be relatively small for retail establishments or have a large tank suitable for large-scale production facilities. The many types of chocolate conching machines allow for the diverse array of chocolates that are found in stores, restaurants, and on many television shows demonstrating cooking techniques.