how long can hops be stored in freezer?

[thedrake]

I'm wondering if there is a good rule of thumb for how long hop pellets should be stored in the freezer in an air tight zip-lock bag? I realize that hop stability varies by hop variety, but what's a good general rule? Should I really increase the amount of hops I'm adding to a beer based on the hop stability index if the hops have been properly stored in a freezer for, say, less than 6 months??

[straight cash homey]

if you get promash there is a hop time degradation calculator that you can use to estimate the adjusted alpha based on starting alpha, temp stored, length of time stored and type of storage (plastic bag, airtight, inert). you can download the trial version and still use the calc if you want. as far as how long to keep them, i have no idea what the limit is. the calc maxes out at 5 years, it says that 7% AA Cluster stored in a plastic bag in the freezer for that amount of time will drop to 2% AA. but they would probably be freezer burned to hell by that time.

[thedrake]

I use BeerSmith and it has a similar hop degradation calculator. Has anyone used one of these calculators for older hops, adjusted hops accordingly in the recipe and ended up with the resulting hop bitterness/flavor they expected? I'm just not sure how confident I should be in the adjusted alpha acid numbers coming out of the calculators in the software. Thanks!

[Bugeater]

I've used the hop degradation calculator in ProMash several times on hops over a year old. Based on the resulting beers it seemed to overestimate the amount of degradation. The beers came out much hoppier than they should have. Part of the problem may have been variances in storage temperatures during that time. I have since switched to freezer storage but still have some of the old hops in there. I'll have to recheck when I get some old hops that have always been frozen.

Wayne