Find out everything about freeze drying technology: how to improve results, drying times and energy useage; calculate costs and find out more about particular products.
The duration of the freeze-drying process
The freeze-drying time is of crucial importance for the utilization of a freeze dryer. However, freeze-drying times vary greatly between different materials, as water content is the main reason for the differences. But other factors also play a role; oranges and tangerines, for example, have extremely water-resistant skin and store water very well. In this case, cutting the fruit is crucial - smaller pieces are easier to freeze dry. Berries with a thick skin are generally also good at retaining water, such as blueberries. Strawberries, on the other hand, are very easy to freeze dry. The following table shows the drying times for medium-sized pieces of about 10 mm at a final temperature of 25°C, 40°C and 60°C. The higher the temperature, the faster the drying process, but slower drying preserves more vitamins and better structure. It is therefore necessary to individually adjust the temperatures and drying cycles according to the desired quality of the final product, which can be ensured by the flexible user interface of the Wave freeze dryers.
The following table shows freeze drying time in hours at different maximum heating temperatures.
The following table shows the nutrients of a fresh and freeze dried strawberry.
The freeze drying process - preparing, freezing, drying, packaging
The process: After the preparing and freezing of the material the drying cycles with different temperature steps are extracting the water out of the product. When finished, defrost the machine to get it ready for a new cycle (around 20 min) and pack the material airtight. PRO-TIP: If the ice at the vacuum chamer is getting warm, you can take it out with your hands and reuse it - for example to rehydrate CBD buds.
The weight of fresh vs. freezedried products
Depending on the water content of the product, the needed time for freezedrying and the weight of the final, freezedried product differ.