Rate of freezing

Culinary Science Laboratory' students are seen analyzing the textural changes in spinach as a function of freezing rate with Prof. Dr. Sibel Ozilgen as a part of the course 'Culinary Science Laboratory' at the Gastronomy and Culinary Arts Department, Yeditepe University. The size and amount of the ice crystals in foods can contribute to several sensory attributes, such as texture and mouthfeel. In general, a slow freezing rate results in large ice crystals. Large ice crystals in foods may rupture the food cells and may cause a loss of natural juice found in cells upon defrosting. The foods get dry and wilted. Large ice crystals also may give a very gritty and lumpy structure to some frozen foods, such as ice creams and frozen desserts. However, rapid freezing results in a large number of ice crystals. These ice crystals are usually smaller in size. Therefore, they cause less cell ruptures than large ice crystals. Rapid freezing is usually favored for the food freezing processes, vegetable and meat freezing being the primary examples.