Freeze-drying is based on a sublimation process (going from a solid state directly to a gas without passing through a state of liquid). The food is put into a frozen state under pressure. Then all frozen moisture is sublimated and removed from it. This process eliminates the water without heating or prolonged drying processes. The food retains its taste, nutrition and becomes lighter in weight making transport easier.

Freeze drying food prevents the deterioration of it and it can be stored unopened for several years.

Mylar was the original packaging of choice for long term food storage. This is however not environmentally friendly and even though the product has been developed to become more focused on the environment, here at Bancasa we have discovered using Grounded Comvac™ pouches which is made from renewable Plantcell technology, and is compostable vacuum pouches the packaging of choice. The pouches have a high barrier to both oxygen and moisture and are fully biodegradable and compostable. The bags are re-sealable. Once opened the shelf life is reduced all though the product will remain in good condition for an extended period of time.

Practically any natural unprocessed food can be freeze dried. More often it is used for vegetables, fruits, mushrooms, meat and fish. This technology can also be used for products such as granulated coffee and other instant drinks, spices, porridge, soups although things like peanut butter and honey is not suited.

With modern technology the process of drying food has evolved immensely with the shelf life of food extended astronomically. The two most common methods for drying are Freeze-dry and Air-dry methods. Both these processes are similar and often the look of the food remains similar. The biggest differences are:

Freeze Dry
Method: Freezing and sublimation
Moisture: 2%-3%
Nutrition: 90%-95% retention

Air Dry
Method: Hot air and evaporvation
Moisture: 5%-7%
Nutrition: 70%-75% retention