What are the advantages of lyophilization/freeze-drying?
Freeze-drying maintains the natural biological and physical properties of the raw material. For this reason, it was first used for the preservation of blood plasma in the Second World War. Not until 20 years later were its advantages discovered for the preservation of foodstuffs because freeze-drying fully preserves taste, aroma, color and shape of raw materials. This led to the development of freeze-dried instant coffee and the freeze-drying of meat for ready meals, as well as of fruit for muesli and chocolate. Thermal drying with high temperatures, on the other hand, leads to changes of the raw materials, temperature-sensitive aromas disappear, proteins coagulate (example: boiling eggs), fruit, vegetables and herbs shrivel up (air-drying). The physical structure is thus destroyed by dehydration and a rehydration of the products is more difficult and can lead to products becoming tough. This is completely different in the case of freeze-drying.