What is freeze drying?
Freeze drying is a special method of removing water from a product. Freeze drying is widely used in the food industry but also in pharmaceuticals. This is done mainly to make the products last longer but also to use the product for other possibilities. Take coffee, for example. Instant coffee is freeze-dried coffee, all you have to do is add hot water and you can immediately enjoy your coffee. Wherever you are. Without freeze-drying the coffee first, you are always dependent on a coffee maker, so freeze-drying offers more possibilities than just preservation. It brings more convenience in some cases (think soup-in-a-bag) but this freeze-drying technique is also used, for example, when books have been affected by water.
Benefits of freeze drying
Of course, we mentioned shelf life just above but freeze-drying has more benefits:
- The taste and nutritional values are better preserved
- the volume decreases
- the weight of the product decreases
- Freeze-dried fruit takes on a brittle texture which gives the product a different mouthfeel and taste experience.
The reason why freeze-dried products have a longer shelf life is because the water has been removed from the product. Microorganisms such as bacteria, yeasts and fungi cannot multiply as easily in a dry environment. It is therefore important to store freeze-dried products properly. How to do that we tell you later in this article.
Disadvantages of freeze drying
Every process has some disadvantages in addition to advantages, and so does freeze-drying. The disadvantages of freeze drying are:
- the structure of the product changes, in the case of freeze-dried fruit this also gives advantages but with some products it can also be a disadvantage
How exactly does freeze drying work?
Why freeze-drying is relatively more expensive is because of the process. Freeze-drying is a type of drying that happens at temperatures below freezing. With fruit, this is done in four steps. First the fruit is prepared for freeze-drying, the fruit can for example be cut into slices, after which it is frozen at a very low temperature. Think of temperatures from -50 to -80 degrees Celsius.
The faster products are frozen the better it is for the product. Freezing fruit quickly creates fewer large ice crystals and, as a result, the ice crystals are less likely to damage the fruit.
After freezing, two drying steps follow, as the formed ice crystals must be removed. The air pressure in the freezer is slowly reduced, creating a vacuum. During this vacuum, the temperature is slowly increased, how much this is depends entirely on the type of fruit. This creates a sublimation where water does not thaw first but evaporates immediately. Then, in a final step, the fruit is post-dried and the fruit is packaged.
Freeze-drying is a perfect way to preserve flavor and nutrients. without using preservatives.
Is freeze-drying safe and does it fit within a balanced diet?
Freeze drying is safe way of preserving food, nothing is added to the fruit and the product cannot spoil provided it is stored properly. By using freeze-dried fruits and fruit powders, everyone can continue to enjoy these delicious fruit flavors to the fullest. However, a balanced and varied diet remains important.
Storing freeze-dried products
As described earlier in this article, freeze-dried products have a long shelf life because the water has been removed from the product. To keep freeze-dried products longer at home as well, it is important to store them properly. This includes keeping them dry and airtight. This can be done by storing the products in a sealed and airtight container in a dry dark environment.
Dryfruit.com
Thank you for reading this article with all the information about freeze drying. You now know exactly how our products are made and how the freeze-drying process works. We hope to have given you more information with this article and have you been inspired? Then take a look in our webshop for the diverse range of delicious freeze dried fruits and fruit powders!
