Putting a piece of paper between the tea and the container is a very traditional way to deal with the problem and is still practiced by many older respectful retailers. I am so delighted to read that you are doing the same.
Immediately after production, a green tea should be about 5~6% water. However, improper subsequent handling often cause higher moisture content at retail. Protecting your buy is a smart thing to do.
In old style packing for Longjing, two layers of paper wrap each 0.6 kg of tea before putting in a tin lined crate. A same size pack of dehydrated gypsum is put in the centre of the crate.
You are right that after refridgeration the tea changes a bit. One way I always do to minimize that and quite successfully is never to open even the first layer of protection after the tea is taken out from the fridge. I let it stand for one day or so to make sure the whole mass is return to room temperature to avoid moisture condensation on the surface of the leaves.
Unless the tea is purchased immediately after production, almost all green tea producers, including tiny family operated ones, put their stock in the fridge before the ambient temperature turns 30. That is why some green tea in the market has been subjected to refrigeration without even the retailers themselves knowing it. Lower price green tea, such as meicha or gunpowder are exceptions.
