Evolution of particle size distribution, flow behaviour and stability during mill ball refining of a white chocolate flavouring paste

The objective of this research was to study the effect of ball milling of a white chocolate anhydrous paste on its particle size, rheological and stability properties. Increasing of refining time reduced the solids particle size and resulted in an increase of paste apparent viscosity and improvement of stability. The parameters of the generalized Casson rheological model used to describe the flow curves showed a continuous increase as refining proceeded. The colloidal stability of the pastes was studied through gravimetric oil separation by both visual inspection and light backscattering acquisition along the sample height and gave comparable results with the most refined samples being the most stable.