How to Extract Fruits?
2. Thermal drying (hot air, microwave, heat pump, vacuum thermal drying)
3. Spray dry
Freeze-drying is to freeze substance which containing a large amount of water to cool it into a solid in advance, and then directly sublime the solid water under vacuum conditions, in this way, the substance itself remains in the ice shelf when it is frozen. And the nutrient elements keeped by freeze-drying is generally the most compare to the other two methods.
But the problem is production cost is too high. Basically, 1kg of fruit powder cost more than thirty dollars, that is so expensive than other drying methods. And also freeze-dried type powder is easy to be eriorate if stored improperly.
Thermal drying is to heat furit and evaporate the water in fruit. It is the simplest and easiet drying method and most important, the production cost is very low.
However, the nutrient elements will be reduced more comparing to the freeze-drying method. Microwave drying will damage the active nutrients of fruit most.
Spray drying is the way after fruit juice or fruit slurry is atomized in the drying chamber, the moisture is quickly vaporized in contact with hot air to obtain a dried product. Generally, water-soluble or instant fruit powder is generally used in this drying method. Most this type of method is used in drink which has a higher request on solubility.