ive been savin the best beans i ever find, over the past 20 yrs.
they are all kept in a oldschool 35mm film canister. nothin else.
in a place they wont be disturbed like a drawer or jewelry box.
for very special beans, i put em in a lil zip, then in the canister.

how long?
i germed 16 year old thai 6 months ago.

your mileage may vary

good luck.