Pineapple takes a long time to freeze dry. If the first test run we did, we found that the small freeze dryer had a bit of hard time, so we lightened the load to see what difference it would make.
Here’s the cost and efficiency breakdown:
One of the most important numbers is the $/lb. It’s interesting to see that the 5-tray freeze dryer can process the same amount of pineapple (measured in lbs./hour) as both the 3- and 4-tray units combined.
Cost per pound:
As you can see, the 3-tray freeze dryer wasn’t nearly as efficient as the 4- or 5-tray freeze dryers. We’ll do other tests to see if this is consistent with pineapple, because other food items haven’t shown this much of a discrepancy in efficiency between the different units.
Pressure and temperature graph:
These graphs are interesting. You can see the red section of the cycle where the drying cycle is complete, but we waited to remove the pineapple. That usually happens when the cycle finished in the middle of the night.