Lyophilization – the revolution is coming?
Lyophilization has recently become a very fashionable concept, but this process is known for at least 70 years. It was first used during the Second World War by the order of the United States government. The American army needed food rations of low weight, and the lyophilized products perfectly fulfilled this condition. They were light, easy to transport and kept fresh for a long time. Later, lyophilizates also conquered the cosmos and the Himalayas.
Lyophilization consists of four main stages: preparation for freezing, freezing, first drying and second drying. The process itself consists of the complete removal of water from the frozen product by sublimation, i.e. a direct transition to the vapor state (omitting the liquid state). The product is first pre-frozen at atmospheric pressure, then it undergoes the process of sublimation of ice, and finally it is dried to the desired final humidity.
Currently, freeze-dried products are becoming more and more popular all over the world, but until recently, mainly soldiers, cosmonauts and mountain climbers were eating freeze-dried meals. Powdered food enjoys the recognition of consumers mainly due to the fact that in 90% it retains vitamins and nutrients, as well as the shape, taste and aromas of the dish. In addition, the lyophilization process eliminates most microbiological contaminants and they are free of water, and thus, no type of microflora develops in them. Freeze-dried products can be stored for several years, which is their great asset. A wide range of freeze-dried products consists of breakfasts, lunches, dinners, but also snacks, fruits, vegetables and many more.