Abstract: | Atomic force microscopy (AFM) has been used to study the surface of chocolate as well as the progress of chocolate bloom over time. Fresh chocolate was found to be relatively smooth but with deep holes. These could be pipes leading deep down into the body of the chocolate, perhaps reaching the filling. After storage for a few weeks, we observed the growth of small drops around these holes. With increasing time, these drops became larger and more structured. After further storage, a crystalline structure and bloom were revealed. These results suggest that bloom growth in pralines is a two-phase process, with drops initially forming on the surface and then bloom crystals nucleating and growing from them. Further, we deduced pipes leading down into the center of the chocolate through which the migration of filling fats can preferentially occur. |