Amberale If you displaced most of the oxygen in the can would that not help with the oxidising
This chemistry thing is going way over my head now. But you are correct I believe: if you flush the can or bag with nitrogen, they will be kept fresh for a lot longer, because thereās no oxygen to oxidise I believe. I donāt think the term ādisplacementā is correct though: I think they fill the bag or tin with nitrogen. I donāt think the oxygen (or hydrogen, or CO2 or whatever) is displaced due to dynamics in the sense that one simply replaces the other.
I donāt know how they fill the can/bag up, but Iām assuming it must be a process of removing the air from it (imagine squeezing the bag with as much as possible) and then filling it up with nitrogen maybe through a one way valve. No idea (nor can I imagine) how the process works for a tin though, and Iām not even sure if what I am saying is even remotely factual to the actual process. š
But Iām also told that, once you open it, the process of going stale happens even faster (no idea if itās true or the reason behind it).