TL;DR: best case scenario, it'll never be true-to-brand unless it survives further good-quality storage.
When you say "beer" escaped from the kegs, you have to realize that once you're at that freezing point, that the liquid fraction you see is a freeze-concentrated liquid. Now if you're saying there's a little something around the gaskets, you probably haven't affected the chemical composition of the beer, but I would worry that you've cracked something in the coupler fitting--but that problem will be obvious once things are thawed and connected. Check for leaks as they warm up.
If you've lost a lot of liquid though, that liquid will have been higher in %ABV than the original beer because of freeze concentration, like you'd get for an EisBock or applejack.
Something to watch out for is to give the kegs a good long time to thaw before testing them. You can develop a ring of ice around the inside at the top that will affect what's coming out the dip tube. I've cracked open many half-frozen corny kegs and a taken apart a few frozen spears, and that's a pattern you see on the inside: ice above, concentrated liquid below, even though the kegs had been "pouring fine"--allegedly.
Now, as to whether the beer is "worth saving".... Having said the above, there is a judgement call. Nothing about freezing or even freeze concentration is going to affect the microbial profile, or introduce anything new (presumes kegs have kept positive pressure!). There are volatiles that are significantly less soluble in frozen water than they are in liquid beer, and it takes time for them to resuspend/redissolve from the headspace. There are also potential impacts to carbonation, as the freezing affects the carbon dioxide carrying capacity of the remaining fluid, however given long enough storage this should even out at well.
There's a question though of how you're presenting it at that point. Even if you give it the time to even out (even a week would probably do the lion's share), it's unlikely to withstand close scrutiny when compared against a fresh keg.
Not sure if you have the right gear, but the beer would be potentially a good candidate for making into a special ice-concentrated one-off, like an EisBock. There may potentially be legal implications depending on your local laws (is it returned beer? must returned beer be disposed of in your jurisdiction?).
Cooking with it is almost certainly an acceptable option, depending on your local laws. I personally find that the quantity the kitchens use is often too small for that to be a viable disposal option for much more than a keg.
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Matt Philip (WeCanDrinkTogether)
Severn ON
(519) 588-3242
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Original Message:
Sent: 01-23-2025 13:49
From: Tracy Converse
Subject: Frozen kegs
My brewery is still under construction, in the meantime I am helping out our local alehouse. We are up in very northern Wisconsin and temps earlier this week were -25. Long story short, extra kegs are kept in a coolbot outside, the owner turned off the small heater in the CB because earlier in the weekend temps were in the mid 30s, he then forgot to turn it back on and now we have some frozen kegs of the house beer which is a bigger (7.6-8% ABV) Brown ale. Beer did escape from the kegs but there does not seem to be physical damage to them. Is this beer salvageable? My thought was possibly useable for cooking as a few dishes are made with the house beer. Thoughts?
Thank you,
Tracy Converse
Head Brewer/Owner
Boulder Jct. Brewing Co.
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Tracy Converse
Boulder Jct Brewing Co
Boulder Junction WI
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