Hops from a freezer unplugged for 9 months?

[Jukas]

So I live in northern ca and we evacuated back in oct due to the tubs fire. Apparently my beer freezer got unplugged shortly after the evac and never got plugged back in. I haven’t been brewing the past year due to life/kid/work stuff so I never noticed this until yesterday.

Obviously the whole thing needs to be cleaned as there is some mildew/mold in the freezer likely from condensation when everything thawed.

I’m wondering about the hops that are vacuum sealed and if they’re still good/usable as I had probably 20-30lbs in storage.

 

[IslandLizard]

Damn, what a bummer!

8 months at ambient temps from 70-100F. At least most was during "Winter" months.

There's a hop storage index for each hop variety, that calculates AA% degradation when stored at room temps. That would surely apply to them. They may have lost as little as 20% to even more than half of their AA% during that time.

Flavor and aroma wise they may have suffered a bit too. Maybe they're not as potent anymore, a few simple tests only can prove what's what.

They should not have turned into cheesy bits if they were vacuum packed or still in original sealed packs. Oxygen exposure would be needed to make them cheesy, which is sped up by higher temps of course. So previously opened, non re-vacuum-sealed bags may be dicey.

 

[bpgreen]

When I started reading your post, my reaction was that you should toss them.

Then I saw the quantity.

Smell them. If they smell good, use them. But, as @IslandLizard noted, you'll probably need to use more.

 

[Northern_Brewer]

There's a hop storage index for each hop variety, that calculates AA% degradation when stored at room temps. That would surely apply to them. They may have lost as little as 20% to even more than half of their AA% during that time.

The two great enemies of hop chemistry are warmth and oxygen. HSI applies to hops at 20C/68F exposed to air - and as IL says under those conditions hops can be losing anything up to 80% of alpha acids (and as a rough guide, most other compounds) per year. However excluding oxygen can get that down to 20% per year (and vacuum-packed in a fridge it's more like 10% per year). Obviously degradation happens faster at the higher temperatures you saw, but the vacuum-packed stuff shouldn't have suffered too much.

Obviously you should bin anything that smells cheesy or "off" and be prepared to experiment with the rest, but I'd start working on a guesstimate that you need to increase recipes by 30% for these hops, and adjust depending on how the first ones work out.

I'd be more worried about anything that wasn't vacuum packed, but even that can be useful. Lambic brewers deliberately seek out hops that are several years old, as they want preserving power but not flavour contribution. Aged hops can be great for things like fruit beers, or even to add a subtle hint of hop to cider etc.