Immersion chilling and freezing in aqueous refrigerating media: review and future trends

Immersion contact chilling and freezing (ICF) in aqueous refrigerating media consists of soaking foodstuffs in a cooled aqueous solution. Binary brine solutions (sodium chloride, calcium chloride) are usually used, and less frequently, ternary or more complex solutions, e.g. water + salt + ethanol or water + sugars, are used. The advantages claimed for ICF include shorter processing times, consequent energy savings and better food quality. This freezing technique nevertheless has a limited rang of application as it is not yet fully developed, in particular because of the problem of uncontrolled penetration of solutes into the food material. Recent advances in the ICF process involve a detailed understanding of multicomponent mass transfer during soaking processes and solution properties at low temperatures. These advances should be of practical benefit, opening the way for new applications in the chilled and frozen food sector. The present paper comprehensively reviews the current state of the art and analyses new prospects for the ICF process. (C) 1998 Elsevier Science Ltd and IIR. All rights reserved.