SchokExtrusion

The aim of the SchokExtrusion project is to replace the conventional, time- and energy-intensive conching process in chocolate production with a continuous double-screw extrusion process that integrates conching and tempering, ensures product quality, and simultaneously significantly reduces processing time, energy consumption, floor space, and personnel requirements.
As a perspective, the goal is to develop the technology from laboratory to pilot-scale, and to transparently demonstrate economic effects, especially for small and medium-sized enterprises (SMEs).

Central research questions concern the relationship between specific mechanical and thermal energy input (SME/STE), residence time and temperature profile, the control of cocoa butter polymorphism (βV), flow behavior, dehydration/degassing, and aroma migration under variable screw configurations. The work is based on a systematic approach that links online-measured indicators (melting behavior, rheology, particle sizes, degree of conching) with extrusion parameters to achieve robust tempering and conche-like aroma profiles. Variants such as dry extrusion, double extrusion, and pre-conching, as well as scale-up from the laboratory extruder to the pilot-plant extruder, are examined.

The economic significance lies in the reduction of energy, floor space, and personnel requirements compared with the conche-batch process, as well as in enabling more flexible production forms for SMEs. Follow-up proposals (e.g., IGF) are planned to systematically address open questions.