Crystallization and rheological properties of soya milk chocolate produced in a ball mill

► Increase in refining time does not have any influence on the crystallization rate. ► Higher pre-crystallization temperature prolonged nucleation time. ► The 90min can be regarded as optimal refining time at the 30°C temperature. ► Higher pre-crystallization temperature and refining time influenced viscosity. The aim of this paper is to define the optimal conditions for the pre-crystallization of chocolate produced in a ball mill, that contains 20% soya milk. Chocolate mass and soya milk are refined in a ball mill employing three refining times (30, 60 and 90min) and pre-crystallization temperatures (26, 28 and 30°C). Increasing the refining time leads to organized chocolate systems with soya milk. The nucleation time of the system refined for 90min and pre-crystallized at 30°C is three times longer compared to that pre-crystallized at 26°C. By prolonging the refining time, the system becomes dominantly viscous due to the refining and homogenization (tanδ>1). Taking into consideration all three parameters, i.e., viscosity, yield stress and the area of the thixotropic loop, a refining time of 90min at the pre-crystallization temperature of 30°C seems optimal.