When it comes to freeze drying time of a certain product, we are also interested in this factor because it reflects productivity as well as power consumption. However, the most important factor when using a sublimation dryer (freeze drying machine) is the quality of the product, the value of the dried product is very high, so the time factor is also a big issue.
Main requirement from freeze drying
The freeze drying method was chosen due to the factor of keeping the original shape and color of the product after drying. Other drying methods have difficulty meeting the shape criteria, some other products are related to color, so it is necessary to use freeze drying. The author gives examples of products that really need to be freeze-dried such as yellow camellia, yellow chrysanthemum, rose buds, high-value fruits like strawberries, durian, … high-value medicinal herbs like Cordyceps mushrooms, medicinal extracts… The freeze drying time for these products is relatively the same, all require 25 – 30 hours to ensure drying quality.
Customers should note that the price of freeze dryers is very expensive, many times more expensive than hot air dryers and cold dryers, so consider carefully before buying the machine. Many products are suitable for sublimation drying, but Should only be used for products that need to maintain their natural shape, color and must have high value.
Freeze drying time is how long
It can be said that, compared to other drying methods, freeze drying always has the longest drying time, but the drying time also depends on the method of each facility. The drying process must be frozen at a temperature of -30oC or lower, followed by the sublimation of the water component in the product when the machine starts the drying mode by vacuuming the drying chamber and gradually increasing the temperature. Therefore, if we perform the freezing step outside the machine with specialized freezing equipment, we can shorten the product drying time. For fruits sliced 1cm thick, flower buds, yellow camellia flowers, lotus tea, solutions…. the freeze drying time usually lasts from 25-35 hours or even longer for large sized products.
The power consumption of the device is quite large, much larger than hot drying and cold drying because the systems in the sublimation dryer such as vacuum pump, deep cooling system, dehumidifying system… all have large power consumption. Therefore, when choosing this high-end drying equipment, we need to know that it consumes a lot of electricity.
Latest addition: Currently, MactechDryer has used a pressure-based drying controller on the new generation of sublimation dryers, so the freeze drying time will be much more optimal than the previous stage control method. For example, drying cordyceps mushrooms can take only 20 hours compared to 30 hours as before.
So with the basic information shared above, Readers also understand more about the factor of drying time for products. Please contact Mactech Việt Nam directly for more detailed advice. Thank you for reviewing the shared information.
