Refrigeration

Abstract

Refrigeration in food processing is the removal of heat from a substance to lower its temperature and/or change the state of water to ice. In an ice cream manufacturing plant, refrigeration is used for various cooling duties (e.g. cooling of ice cream mix) or, most importantly, for freezing of ice cream. At the same time the product is being cooled or frozen, the transfer of heat during refrigeration involves the cooling medium gaining energy (heat). Thus, “refrigeration” is the reverse of “heating,” with both occurring simultaneously and being dependent on the same principles and factors of heat exchange. The ice cream industry typically uses the term “refrigeration” to mean the process of cooling to temperatures between 4.4 and -34°C (40 and -30°F). “Chilling” is a term typically used for lowering temperature without freezing being involved (as in cooling the pasteurized mix), but often the terms refrigeration and chilling are used synonymously.