Freeze-Drying - Application in Food Processing and Biotechnology - a Review

Freeze-drying (lyophilization) is a drying process in which the solvent (usually water) and/or the suspension medium is crystallized at a low temperature and thereafter sublimated from the solid state directly into the vapor phase Freeze-drying has become one of the most important processes for the preservation of heat-sensitive biological material Today, the field of its applications ranges from relatively simple preservable food, over complex biotechnological or pharmaceutical products, to proliferating bacteria and fungi In addition to food products (coffee, tea, crispy fruits and vegetables, ingredients for ready-to-eat foods and some aromatic herbs) Although today a great variety of foods, pharmaceuticals, etc. are produced by lyophilization, a successful application for long-term preservation of a living system, like e.g. cells, is still one of the greatest challenges for scientists in this field