Effect of refining and conching on chocolate properties 1. Particle size distribution and viscosity

Talbot G., Slager H., Smith K.W., Effect of refining and conching on chocolate properties 1. Particle size distribution and viscosity, Innovations in Food Technology, February 2008

If chocolate was produced by simply mixing the ingredients together before tempering and moulding, a very poor chocolate would result. There are two reasons for this. First, the human palate is able to detect particles which have a diameter of more than about 25 microns. Without any process of particle size reduction taking place the size of the particles in the non-fat solids (sugar, cocoa powder, and milk powder) would be much higher than that and so the chocolate would taste gritty. So a particle size reduction process, known as refining, is necessary. Second, the cocoa solids in their native state have quite an unacceptable taste which is removed by a process known as conching. This article explores further.