Ever wondered why some chocolate bars are o' so smooth? Well, there is science involved behind it.
This involves two things; the particle size (in microns) & the fat content of chocolate aka cocoa butter.
The human palate cannot not distinguish between two particles when they are less than 30 microns. This is just science, we didn't come up with it. The machine which most chocolate makers use to achieve this fine particle size is the reliable stone grinder. We too refine our cacao in it, however, as we grew we have upgraded to a much larger and more precise machine.. the ball mill.
Measuring the particle size is done with the use of a hegman gauge. Basically, you take a few dabs of chocolate and apply it in the very fine groove carved out in the gauge. You would then take another steel scale and apply pressure and spread the chocolate across the grove to measure the particle size.
But there is a problem with it. Grinding chocolate only in a stone grinder will take the particle size down to 22 odd microns, but the particle distribution is all over the place. Meaning, there could be particles in batch that are at 22 microns & 35 microns are the same time. The distribution is uneven. Hence, chocolate that is ground up in only a stone grinder usually has a hint of a course texture.
When a machine like a 3 roll refiner or a ball mill is used, a more even particle distribution is achieved. We have a ball mill because that's what gives us the best result.
In addition the the particle size of the chocolate, the fat content also dictates how well the chocolate melts on your palate. Hence the more cocoa butter present, the faster and smoother the mouthfeel of chocolate. We use additional cacao butter in all of our chocolate. The butter is pressed in house from the cacao beans we procure.