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Many correlations in the literature have been proposed to predict the external heat transfer coefficient, but most of them are suggested for batch operations. This paper aims to experimentally investigate a steady state condition (usually found in industrial processes) of mixed vessels equipped with a four 45° pitched-blade turbine and vertical tubular baffles to determine the external heat transfer coefficient. An empirical correlation based on the work of Sieder–Tate [Ind. Eng. Chem. 1936, 1429–1435] for a steady state condition using standard configuration of a mixing system is being proposed. A sucrose solution of 20% and 32% concentrations (w/w) and a mixing apparatus with a 50 L cylindrical flat bottom vessel are employed. Water was used as heating fluid running inside the vertical tubular baffles with an inlet temperature range from 25 to 45 °C and an impeller speed from 30 to 330 rpm. A new fit correlation was proposed based on the Sieder–Tate modeling, yielding good agreement with experimental data in steady states with deviations of less than 15% between observed and predicted external heat coefficients.

Inulin is a storage polysaccharide present in more than 30,000 vegetable products, including chicory roots, that are considered suitable for industrial application. The objective of this work was to evaluate the influence of temperature and the soluble solids concentration on the rheological behavior of a concentrated inulin solution obtained from a centrifugation process from chicory roots, after freezing at −24C. For all the evaluated soluble solids concentrations, inulin solutions showed a rheological behavior of a highly pseudoplastic fluid, with high resistance to flow at low strain rates followed by a breakdown of the structure when the shear rate increased. The effect of temperature on the apparent viscosity of inulin solutions can be represented by the Arrhenius equation. The rheological behavior of inulin solutions can be represented by the Herschel–Bulkley, Casson, Cross and Power Law equations, where the consistency index increases as temperature rises and the soluble solids concentration as well. PRACTICAL APPLICATIONS The main objective of this work was to analyze the rheological behavior of a concentrated inulin solution obtained from chicory roots, to check the possibility of its application to obtain powder inulin. The concentrated inulin solution was obtained by diffusion in hot water, followed by concentration by evaporation and phase separation conducted by lowering the temperature (−24C) and centrifugation at a velocity of 10,000 rpm for a time interval of 15 min. However, this solution is still going to be processed. Therefore, it is important to know its rheological behavior. The influence of temperature and the soluble solids concentration on the rheological behavior of the concentrated inulin solution was also studied.