An analytical relationship of concentration‐dependent interfacial solute distribution coefficient for aqueous layer freeze concentration

Abstract

Freeze concentration (FC) is a subzero temperature solute concentration procedure, favoring the retention of high quality compounds such as food ingredients and biological materials. It is known that modeling solute inclusion in the ice layers or ice crystals formed in a convective environment requires the solute distribution coefficient function. The fluid flow velocity, ice‐growth rate and solute concentration are influential on this function. Some literature has reported certain expressions of the function, which are relatively complex. Here, an explicit format of this function has been derived for single solute system, and found to be satisfactory in correlating a wide range of experimental data on sucrose solutions for both the controlled flow layer crystallization process (flow in between two cooling plates) as well as the falling film crystallization process. This expression has captured the fundamental aspects of mass transfer, and it is relatively simple which should be very useful for correlating FC parameters and for simulating the layer FC processes. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1334–1344, 2015

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