Continuous-action crystallizer-cooler for sweetened condensed milk products

The article considers the issues of uncontrolled lactose crystallization in sweetened condensed milk. The work analyzes the factors that influence the size of lactose crystals, such as temperature, stirring, seed crystals, ultrasound, electric and magnetic fields, as well as the presence of impurities. It also substantiates the necessity of creating optimal conditions for the formation of a large quantity of small crystals (up to 10 μm) by means of two-stage cooling. The authors present the design of a crystallizer-cooler, consisting of two main parts - a spiral section and a screw section - ensuring a continuous crystallization process and controlled growth of lactose crystals. The proposed apparatus improves the quality of sweetened condensed milk products by rational regulating of the temperature regime and mechanical effect on crystallization process by usining a propylene glycol cooling system.