Sublimation products is drying food using rapid cooling and freezing the water contained in the vacuum. As a result of the product to evaporate almost all the moisture (water) and its moisture content does not exceed 8-10%.
Sublimation (sublimation, freeze drying, lyophilisation) is a transition of substance from a crystalline (solid) state directly to the vapor (gas) without passing through a liquid state.
The process of sublimation is a very fast (or rather sharp) cooling the initial product to a low temperature (about -50 0C and below). In fact, the sooner the product is frozen, i.e. the higher the freezing rate, the smaller of the watercontained in the raw product, the formation of ice crystals which due to their microscopic size not cause damage to the tissues of the product. When rapid freezing they do not tear the tissues and cells of the product. On the contrary, the product is frozen slowly, larger crystals are formed of ice, which break the tissues and cells of the product, and it loses its original shape and form.
Then the original product is placed in a vacuum dryer. Do it with the intention to freeze the moisture out of it in the form of water. The water passes from solid to gas, bypassing the liquid state. Ultimately all these actions from the product evaporate almost all the moisture (water) and its moisture content does not exceed 8-10%. However, it is completely (almost 99%) is preserved all the vitamins, minerals, enzymes and other biologically active substances, since the sublimation process eliminates heat treatment.
Freeze-dried product can be stored in the refrigerator or at low temperatures, it can be stored at room temperature. To restore the freeze-dried product add plain water.
Storage freeze-dried product is not always. He also has a limited shelf life (storage time). For example: vegetables and berries are stored for about 2 years, and dairy products – 13 months.
Sublimation is exposed to berries, fruits, vegetables, juices, dairy products, cereals, meat, fish, etc products. As a result of sublimation, they become either a powder (liquid foods: juices, milk, etc.), either in whole food or part thereof (all other solids).
Sublimated products have a lot of advantages.
– food industry,
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