The ground coffee beans are then dissolved with hot water to extract the flavor and aroma. The coffee becomes powder by taking out all the water through either freezing or evaporation.
In freeze-drying, the coffee extract is frozen to about – 40°C and cut into granules. The smaller frozen granules are dried in a mid-temperature vacuum and under vacuum. The quality of the aroma and flavour are protected by the very low temperature and gentle drying conditions.
As the frozen coffee granules warm up, the frozen water rapidly expands into a gas without it becoming liquid along the way, in a process called sublimation. Sublimation allows frozen foods to be dried without ever having to melt by avoiding a breakdown of cell structure.
Once all the water molecules have successfully sublimed, what is left are dried coffee granules. Finally, the soluble coffee is packaged into either glass jars or sachets.
Freeze drying instant coffee
