Cooling Caramel in Ethyl Alcohol: Constructing a Mathematical Model

Abstract

Introduction. The process of air-cooling caramel remains one of the most complicated issues of contemporary food industry, since it is time-consuming and requires multi-level cooling units. Therefore, the development of an innovative method of cooling caramel in “cold” potable ethanol is an urgent task the modern food science has to solve. The method op-timizes and intensifies the technological process, as it reduces production areas by eliminating some technological stages and complex units of metal-intensive and energyintensive equipment. It gives caramel antiseptic properties and a perfectly smooth, shiny, and dry surface. Study objects and methods. The research objective was to develop a fundamentally new and promising caramel technology. The experimental studies on the production and cooling were performed in a mixing and forming multi-unit with a high-performance cooling chamber. The chamber had functions of automatic measurements and control of the main parameters of the cooling process. The research used “cold” potable ethanol. Results and discussion. The paper introduces a mathematical model of the process of cooling caramel in ethanol. It includes heat transfer processes in alcohol, in the caramel mass, and on their border. The model was based on equations of transient heat conduction in a sphere. The process of heat exchange with the environment, i.e. alcohol, was characterized by the coefficient of heat transfer from the sphere. The model parameters included dynamic viscosity, density, thermal conductivity coefficient, and specific heat capacity. Based on the experimental data, the parameters were ap-proximated as a function of temperature by a cubic polynomial. Conclusion. The developed mathematical model made it possible to estimate the radial temperature distribution of caramel in the form of a sphere during its convective cooling in ethanol. The model also predicted the change in the average volume temperature of the caramel and energy costs depending on the cooling period, the flow speed of the ethanol, the thermophysical properties of the caramel and the cooling agent. The proposed mathematical model can be used to calculate the required consumption of ethanol for cooling and backwater of the caramel production line.