Pre-dried refiner flakes allow very short or even continuous conching of milk chocolate

Chocolate conching is usually still performed in a time consuming batch process. For milk chocolate, its main purpose is to remove water and to adjust flow properties. As the conch is not an efficient dryer and flow properties are mainly influenced by shear treatment, the objective of this study was to separate and optimise both processes. Prior to liquefaction, refiner flakes were dried to <0.6% of water in an oven, which allows to omit the dry phase of conching. Conventional conching of 5 h was then reduced to a liquefaction process taking 20 min. Alternatively, continuous processing was tested applying a high shear mixer REFLECTOR^®. Sample properties were very close to a standard. Only continuous liquefaction at very high throughput resulted in slightly increased viscosity. Sensory analyses just found negligible differences. Thus neither pre-drying nor short or continuous liquefaction had a negative impact on product quality.