[tesgüino]

On Sunday, I lost power in my induction hob after about a half hour of boil time. It was an all late hopped ale, so no hops in yet. After a delay, I chilled to about 80 degrees and transferred 12-1/2 gallons of wort to carboys and stuck them in my cold crashing fridge. There won't be an opportunity to finish the boil until this weekend. What are the down sides of this? I think I remember hearing that souring or infection can be a problem even chilled. My sanitation was good, but not great. The kettle was uncovered for an hour or more while I attempted repairs and I transferred about 5 gallons of the wort to an unsanitized five gallon pot so that I could lift the kettle off the hob.

And a side note, an internal fuse blew on the hob. Probably because of a power surge from a nasty storm that blew through.   

[Slowbrew]

You could have picked up an infection but assuming you've kept it reasonably cold and sealed up after transfer it likely won't be too bad.  You plan to bring it back up to a boil which should kill off any infection.

You may lose a bit sugar to any bugs that took hold and possibly pickup some extra flavors but I don't know that I would too concerned.

Heck!  It will still be beer and you may get something very good and unique along with a story to tell.  You never know.

Paul

[Stevie]

You could have picked up an infection...

Of botulism spores. I wouldn't use it. Maybe if it had been hot packed similar to no-chill brewing, but I wouldn't trust it.

[kramerog]

You could have picked up an infection...

Of botulism spores. I wouldn't use it. Maybe if it had been hot packed similar to no-chill brewing, but I wouldn't trust it.

Botulism only grows anaerobically.  Do you have any reason to believe that the wort was anaerobic?

[Stevie]

He said he put the wort in carboys, so I guess it depends on the amount of headspace and if something consumed the oxygen in the headspace.

The risk is small, but real enough to where I would scrap the wort and start a new.

[HoosierBrew]

Personally, no way I'd resume boiling week old wort, regardless of how it was handled. Even with stellar sanitation practices, it seems next to impossible that the wort wouldn't show any sign of infection whatsoever (botulism arguments aside). If so, boiling wouldn't fix an 'off' flavor. Buy a little more grain and make it fresh.

[natebrews]

I am certainly no expert, but I think botulism takes more than a week to be a problem (would you eat something that had been in the fridge for a week?).  I think there was an episode of basic brewing about this once.  I think no-chill guys do it all the time, and the 100C that the wort gets to boiling isn't going to do much to stop botulism spores that are in there.

Additionally, people do spontaneous fermentations by just making wort and putting it into a fermentor after exposing it to the air.  If he had just said he was making a spontaneous ferment sour beer nobody would think twice (well, maybe some would).

I think the more major concern would be flavor spoilers, but those should be apparent if you taste it. 

[Stevie]

Article from Chris Colby. I trust his assessment.

http://beerandwinejournal.com/botulism/

As for spontaneous fermentations, the theory there would be the microflora would lower the pH to a level low enough to prevent the toxin from being produced.

[natebrews]

Fair enough, but it looks like it would be irrelevant anyway if he is going to boil it again. 

From the article:
---snip---
 And, if the food is heated to 185 °F (85 °C) for 5 minutes before serving, the botulinum toxin will be denatured, and the food is generally considered safe. [Some sources give a more conservative recommendation of heating the food to 212 °F (100 °C) for 20 minutes.]
---snip---

In all honesty, I would probably chuck the wort and just make some more.  You could brew it into beer and it will probably be fine, but it if isn't then that is a lot of time down the tubes to save another hour of mashing.

[Stevie]

Good eye.

But yeah, even if safe, dump it and start over. What are you loosing $20 and a couple of hours. You'd need to throw another 3 hours at it to get to a point where you can ferment and even then it might be a questionable outcome.

[brewinhard]

Off-flavors alone are enough reason to dump it and start over.

[beersk]

OP, you should've just added all your hops when the burner went out and let sit for 30 minutes. A 30 minute boil was sufficient to begin with.
I'd scrap the wort...

[tesgüino]

Pretty unanimous. Have to dump it. Curious though, what are the bugs (or whatever it might be) that cause the off flavor in wort stored in a refrigerator for one week?

[Stevie]

Lacto, Brett, and wild Sacc would be most likely flavor ruining bugs

[tesgüino]

So, why don't those bugs change the flavor of other sugary things (say like homemade ice tea) that have been in the fridge for a week?

Not arguing. Enough people have made the same point that I don't doubt it's correct. Just want to understand it.