How are freeze-dried vegetables made?

The production process of freeze-dried vegetables mainly includes the following steps:

Picking: Choose to pick vegetables when their nutrient content reaches its peak. Winter vegetables are usually harvested during the overwintering period until flowering, while spring vegetables are harvested during the early maturing period.

Cleaning and pre-treatment: The harvested vegetables need to be sent to the cleaning workshop for cleaning to ensure hygiene and quality. Pre-processing includes peeling, shredding, and cutting into pieces, customized according to the characteristics of different vegetables.

Freeze drying: Send the processed vegetables to the freeze-drying workshop for freeze-drying treatment. This process involves rapid freezing at low temperatures and evaporation of water at ultra-low temperatures, with the main purpose of preserving the color, taste, and nutritional content of the vegetables.

Packaging: Freeze-dried vegetables are packaged after cooling, usually using aluminum foil plastic bags as packaging materials to ensure freshness and food safety during storage.

Quality inspection and storage: Packaged freeze-dried vegetables need to undergo quality testing, including appearance, moisture content, heavy metals, and other indicators. Qualified products should be stored in a low-temperature, dry environment, and protected from moisture and sun.

The principle of freeze-drying technology is to first freeze food at low temperatures, and then heat and dry it under vacuum conditions so that the water formed by freezing in the food directly changes from solid to gaseous and evaporates, hence it is also known as sublimation drying. The advantage of this method is that it can preserve the nutrients of food intact and the storage time can be very long.