Yingtai: Application of Vacuum Freeze-Drying Technology in Seafood Products

Yingtai: Application of Vacuum Freeze-Drying Technology in Seafood Products

Vacuum freeze-drying technology is a complex method that combines freezing and vacuum drying, widely used in the food industry to preserve heat-sensitive materials. This technique first crystallizes the solvent (usually water) at low temperatures and then sublimates it directly from solid to gas, effectively retaining the original nutritional components, color, flavor, and structure of the food.

Advantages of Freeze-Dried Foods

Freeze-drying technology has become a significant method in food preservation due to its ability to maintain food quality. It is suitable for various types of food, including meats, vegetables, fruits, fungi, and powdered substances. This process not only preserves the freshness and nutritional value of the food but also extends its shelf life, making it particularly suitable for perishable bioactive substances that are not amenable to high-temperature processing. The advantages of freeze-dried foods include:

1. Nutritional Preservation:

   Freeze-drying technology excels in retaining functional components such as vitamins, antioxidants, and fatty acids, helping to delay lipid oxidation during storage and maintain the functional and nutritional value of food. For example, studies on freeze-drying human milk show that, although there is a slight impact on total antioxidant capacity, the effects on lactoferrin content, fatty acid composition, and lysozyme activity are minimal. Additionally, freeze-dried human milk can maintain most of its bioactive substances stable under certain storage conditions.

2. Maintaining Texture:

   The original texture and flavor of food are preserved after freeze-drying. Because the microstructure of the food remains unchanged during the freeze-drying process, rehydrated foods can regain their original texture and flavor. This allows freeze-dried foods to provide a sensory experience similar to that of fresh foods.

3. Convenient Storage and Transportation:

   Freeze-dried foods have significantly reduced volume and extremely low moisture content, making them easier to store and transport. Furthermore, since microorganisms cannot survive and reproduce in a dehydrated environment, freeze-dried foods have a longer shelf life. This makes them ideal for convenience foods, suitable for travel and outdoor activities.

4. Good Rehydration Performance:

   Freeze-dried foods have excellent rehydration properties. Simply adding an appropriate amount of water allows the rehydrated freeze-dried food to restore its original texture and taste. This not only facilitates storage and transport but also enables quick recovery to its original state when needed.

5. Increased Variety and Application Areas:

   The application range of freeze-drying technology is extensive, suitable not only for processing fruits and vegetables but also for drinks, seasonings, and other food products. Additionally, freeze-dried foods can be used in medical and health sectors, such as freeze-dried pharmaceuticals and health products. Moreover, freeze-drying technology is applicable in military, aerospace, and other specialized food supply areas.

6. Environmentally Friendly:

   Compared to traditional heating processes, freeze-drying occurs at low temperatures and results in less environmental pollution. Furthermore, the rehydrated products obtained are reconstructed products with improved shape and texture properties, which are easier to process, recycle, and handle in an environmentally friendly manner.