Painful punishment! Although I use beans, I find rolling the top up tight and then putting a rubber band around the bag works well enough.
I know people, who buy ground, who put the grinds into a tupperware type box and keep it in the fridge or freezer. I think keeping the grounds cold/frozen to help preserve them is a myth - the moisture and temperature changes will ruin them, and "decanting" the grounds unnecessarily exposes them all to air. It's not wine
yeah, Freezing grounds is a mythn. Plus generally dont' want to keep it in an airtight container as it prevents carbon dioxide from escaping. which ground coffee will bleed off. you want some to escape because too much trapped int he bag isn't great for the coffee either.
Thats why coffee bags, especially pre-ground cofffee bags will have that one way valve on them. They let air out, but not in. lets CO out, while preventing O2 in
I usually do what you do. wrap the bag closed. Use an elestic to keep it sealed. This bag was just that bad;
