It is not a hot summer day and it is hard to comb the cherries. However, we want to make sure that our freeze-drier will not be afraid of anything when we test the prototype. Besides, who would want to mess with cherries when you can buy frozen ones and especially a version with the stones removed.
Note: This test was performed on an earlier model of the AMARU lyophilizer. We have made several improvements since then and today the capacity would be higher and the process faster.
Preparation
Thanks to the choice of packaging (2.5 kg bags), preparation was not difficult. Just dump the cherries onto the produce tray and make sure that ideally each cherry is at the bottom of the tray. It is thus necessary to break up some clumps of frozen pieces. However, this will not apply to fresh cherries. A total of 5 kg (two bags) was easily accommodated by four shelves.
Freezing
Again, by choosing cherries already frozen, there was less work. The cherries were at a temperature of around -4°C when they were picked and it took less than 7 hours to reach a temperature below -30°C. In the case of a larger quantity and an unfrozen mould, more time would have been needed.
Drying
In the case of drying, the frozen option is no longer helpful. The cherries resist drying because they have a skin and the water can only leave where there is a hole after pitting. This is probably why it took about 27 hours to dry, even though the machine was not full.
Result
The cherries are still a little sticky even after drying completely. Not surprising, as they are acidic and removing the water only concentrates the sugars and acids they contain. Therefore, it's not even a particularly interesting taste experience - every dried cherry is enormously sour... maybe too much.
Rehydration
Of course, cherries cannot be returned to their original appearance. This is only because of the holes left by the pitting process, no matter whether the pitting is done by machine or by hand. However, it is possible to rehydrate them quite well and one does not even need to tweak the water ratio, as is the case with milk lyophilizates.
Uses
Dried cherries are the ingredients. On their own they are not of much use because of the extreme sour taste. They can easily be ground into a powder with a blender and used as a garnish - sprinkles. Of course, they can always be taken out of the packaging and used for a smoothie or other cocktails. After a few dozen minutes of rehydration in water, I wouldn't be afraid to use them for stuffed dumplings as well :)
