Hi,
I got to a same point when I wanted to drop the plastic bags.
Quite a frustrating experience when everything was so perfect with the bags
Well, I got a herb drying rack (a frame with legs and net) and wrap them up in consecutive attempts in baking paper, cheese cloths, aluminium and kitchen towels plus moved them up and down in the incubator (old fridge with lightbulb in it).
It never came up as nice as from plastic bags...
the closest I got was a layer of baking paper, and two layers of kitchen towels that I got wet every 4-8 hours to keep the moisture in.
Tempeh was nice, but it did not smell as nice, middle was sometimes undone, and the appearance was sub-par. plus the tempeh eats through the paper and towels too...
well I am not going back to plastic. Next one I try will be a glass tray with some wet towels on the top, we will see how it will turn out. (wife said no to aluminium covers...)
T