Freeze-drying or lyophilisation is an industrial technique used for food preservation.
The process of freeze-drying freezes the water molecules present in the dry matter and deforms them to ice crystals. The best-known example is instant coffee. However, this technique is easily applied to vegetables, fruit, herbes and even flowers as well and it has quite some advantages : taste is preserved, storage life is significantly prolonged and both weight and volume are reduced. All the more, using this technique will prevent from developing micro-organismes due to the dry atmosphere. On the downside, the structure changes completely and the application of this technique remains complex.