Why will we choose to freeze dry instead of hot air?

Why will we choose to freeze dry instead of hot air?
We must learn to distinguish the difference between freeze-dried and hot-air dried pine mushrooms in order to better select high-quality pine mushrooms and ensure that the products purchased are high-quality pine mushrooms. Let's take a look at the differences and nutritional differences between the two:
The vacuum freeze-dried pine mushroom is different from the general AD hot air dried pine mushroom. The main advantages are:
1: The shape of the vacuum freeze-dried pine mushroom is well reduced to the shape of the raw material, the morphology does not change, and the cell tissue is not damaged.
The shape of the AD hot air drying has been deformed, wrinkled, and the cell tissue has been damaged.
2: Vacuum freeze-dried pine mushrooms preserve the taste of fresh wild bacteria, and almost no damage to the nutrients of the food. More than 90% of the fresh pine mushrooms are preserved.
AD hot air drying products, except the taste is very different from fresh pine mushrooms, basically 80% of the nutrients have been lost.
3: The moisture content of vacuum freeze-dried pine mushroom can generally reach 8% or less, prolonging the storage time. 14kg fresh pine mushroom can only be used as 1kg FD freeze-dried pine mushroom.
The moisture content of AD hot air dried pine mushrooms is generally above 15%, and its storage time is much shorter than that of freeze-dried pine mushrooms. Generally, about 4kg of fresh products can be made into 1kg of dry goods.
The characteristics of the lyophilized product: fresh pine velvet containing a large amount of water, previously frozen at -40 ° C into a solid, and then under vacuum conditions, the moisture in the pine velvet directly sublimated from the ice crystal state, the dry matter remains in the frozen state In the ice shelf, the loss of nutrients such as protein and microorganisms is extremely small. The finished product is sponge-like, without shrinkage, the volume is unchanged, the original biological and chemical properties are basically unchanged, and the shape, color and taste of the bacteria are well maintained, and it is easy to store for a long time. Soak in water for about 30 seconds to quickly restore to the state before lyophilization.
Hot air dried pine mushroom can only let us eat its body, and freeze dried pine mushrooms, let us complete