The Application of Low Temperatures in the Food Concentration Processes

Primjena niskih temperatura kod procesa koncentriranja namirnica spriječava gubitak tvari arome i drugih degradativnih promjena, te produljuje rok trajanja namirnice. Koncentriranje zamrzavanjem je proces koncentriranja tekuće i polutekuće namirnice izdvajanjem vode u obliku kristala leda. Proces izdvajanja vode se odvija u dvije faze, prvo dolazi do kristalizacije vode u obliku leda iz vodenih otopina, nakon čega slijedi separacija nastalih kristala leda iz koncentrirane otopine. Ovaj rad istražuje, osim samog nastanka kristala leda i njegovog izdvajanja iz koncentrirane otopine, čimbenike koji utječu na nastajanje i rast kristala, te promjene tijekom skladištenja koncentrirane namirnice koje također utječu na kvalitetu namirnice i njenu trajnost.The use of low temperatures in the process of concentrating foods prevents the loss of aroma substances and other degradative changes, and extends the shelf life of the food. Freezing concentration is the process of concentrating liquid and semi-liquid food by extracting water in the form of ice crystals. The process of extracting water takes place in two stages, the first is the crystallization of water in the form of ice from aqueous solutions, followed by the separation of the formed ice crystals from the concentrated solution. This paper, apart from the formation of ice crystals and their separation from the concentrated solution, explains the factors that influence the formation and growth of crystals, as well as the changes during the storage of the concentrated food that also affect the quality of the food and its durability