Immersion chilling and freezing: Phase change and mass transfer in model food

Abstract

The influence of immersion chilling and freezing process variables (temperature, concentration, agitation) on phase change and salt gain, was studied on a gelatin gel dipped into a NaCl solution, with particular emphasis on unsteady state (first hour). Under freezing conditions, water loss was <2 g/100g initial gel and salt gain remained low (<1 g/100g initial gel). Salt penetration was hindered by formation of an ice barrier, which was favored by high concentration and low temperature. Under chilling conditions, salt gain was higher (up to 2 g/100g initial gel), and was enhanced when temperature or concentration increased.