What Is Freeze-Drying and Why Is It Used?

Freeze-drying is one of the most advanced food preservation methods, which involves removing water from products at low temperatures and under reduced pressure. This process occurs in three stages: freezing, sublimation, and desorption, allowing ingredients to retain their nutritional properties, texture, and taste.

Freeze-drying is widely recognized in the food, pharmaceutical, and cosmetic industries because it extends product shelf life without the need for preservatives. However, many people wonder whether this process negatively impacts the nutritional value of food, especially the content of vitamins and minerals. In this article, we will clarify all doubts and separate facts from myths.

How Does Freeze-Drying Affect Vitamins and Minerals?

One of the biggest advantages of freeze-drying is that it takes place at low temperatures, preserving the structure of nutrients. Unlike traditional drying methods, such as convection or thermal drying, freeze-drying does not cause the degradation of most vitamins and minerals.

Water-soluble vitamins, such as vitamin C and B vitamins, are the most susceptible to loss during heat treatment. However, because freeze-drying does not use high temperatures, their content remains almost the same as in fresh products. Meanwhile, minerals such as calcium, magnesium, iron, and zinc remain unchanged because they are not affected by temperature or oxidation.

Which Vitamins Are Most Resistant to Freeze-Drying?

Not all nutrients react to freeze-drying in the same way. Fat-soluble vitamins – A, D, E, and K – are highly resistant to external factors. As a result, their levels in freeze-dried products remain virtually unchanged.

Other stable vitamins include:

  • • Vitamin B2 (Riboflavin) – withstands freeze-drying well and does not degrade.
  • • Vitamin B3 (Niacin) – remains almost entirely preserved in freeze-dried products.
  • • Vitamin E – as an antioxidant, it remains stable during preservation processes, including freeze-drying.

Thanks to this, freeze-dried fruits, vegetables, and dairy products maintain their high nutritional value, making them an excellent source of vitamins for those committed to a healthy diet.

Does Vitamin C Degrade During Freeze-Drying?

One of the most common myths is that freeze-drying significantly reduces vitamin C content. It is true that vitamin C is one of the most unstable vitamins and degrades under exposure to light, heat, and oxygen.

However, studies show that freeze-drying preserves up to 90% of the vitamin C found in fresh products. This is a much better result than traditional drying methods, where the loss of this vitamin can reach 50-80%. For comparison, boiling vegetables can cause vitamin C losses of up to 70%.

Which Minerals Remain in Freeze-Dried Products?

Unlike vitamins, minerals are very stable and do not break down during freeze-drying. Calcium, magnesium, iron, zinc, potassium, and sodium remain in freeze-dried products in nearly identical amounts as in their fresh counterparts.

This makes freeze-dried fruits, vegetables, and meats an excellent source of essential elements that support the body’s proper functioning. Additionally, freeze-dried foods retain their fiber content, making them a great choice for those maintaining a healthy diet.

Freeze-Dried vs. Dried vs. Frozen Food – Which Is Best?

Many consumers wonder which food preservation method is best in terms of nutritional value. Here’s a quick comparison:

  • • Freeze-drying – retains up to 98% of nutritional value, including vitamins and minerals.
  • • Freezing – preserves nutrients well, but some vitamin losses may occur during thawing.
  • • Traditional drying – can lead to the loss of up to 50% of vitamins, especially heat-sensitive vitamin C and B vitamins.

In terms of nutritional value, freeze-drying wins in most categories, which is why it is widely used in the production of high-quality food products.

Is Freeze-Dried Food as Healthy as Fresh Food?

While nothing can replace fresh fruits and vegetables, freeze-dried products are one of the best alternatives. They have almost identical nutritional composition, while also being convenient to store and maintaining their properties for a longer time.

It’s also worth noting that freeze-drying removes water, meaning that nutrients are more concentrated. This means that 100 g of freeze-dried strawberries provide more nutrients than 100 g of fresh strawberries because they lack water content.

Conclusion

Freeze-drying is one of the best food preservation methods, allowing for the retention of almost all nutrients. Vitamins such as A, D, E, and K remain intact, and heat-sensitive vitamin C is significantly less lost than in other processing methods.

With freeze-drying, you can enjoy healthy food all year round without worrying about the loss of nutritional value. It is an excellent solution for athletes, travelers, healthy eaters, and companies looking to offer the highest quality food products.