Dangerous chemical reaction?

[QJoshH]

I'm an intermediate extract/specialty-grain brewer, and recently installed a Johnson Temp Control unit on a chest freezer for fermenting. First batch was a Kolsch, based on Palmer and Zainasheff's recipe. Living in the steamy South, I set the Johnson for 60 degrees (garage temp is 90+) a couple of weeks ago to test... lots of variation in temp (53-65), but otherwise operating adequately.
Saturday night I brewed, then placed my 6.5 gallon glass carboy in the freezer. Sunday morning I checked and found that the stopper and airlock had worked its way out, leaving the carboy open. This happens fairly often for me... no matter how carefully I dry the stopper and mouth of the carboy, it takes some time for the stopper to "set" in the carboy (tips here?). Fermentation appeared active... good krausen.
Unfortunately, the fluid (StarSan) had spilled from the airlock, and I had dumped all my StarSan after cleaning up the night before, so I put a couple of drops of bleach in the airlock and topped off with purified water. All well on the yeastern front when I checked Sunday evening: bubbling away nicely.
However, when I opened the freezer this morning (Monday), I was almost knocked down by a pungent, acidic smell that burned my nostrils and took my breath... what's happening here? Is this just the concentration of carbon dioxide in an enclosed freezer, or has there been a chemical reaction with the bleach? Or has this batch been horribly contaminated? Obviously I'm naive to the chemistry that might have taken place, but want to be sure that I haven't created something dangerous.
Looking forward to moving to all-grain soon, but not until I can get the kinks out of my basic brewing techniques!

 

[evrose]

Dude... um... BLEACH in the airlock?

Hard to say with 100% certainty, but that smell could be chlorine gas from the bleach. CO2 is odorless, so it wasn't that. Chlorine from the bleach is NOT odorless and can be dangerous in high concentrations.

Is there any chance any of the bleach got in to the fermenter? If so, I wouldn't drink it.

If you don't have starsan, use vodka.

There's really no reason to EVER use bleach in ANY part of the brewing process. There are better cleaners, and way better (safer) sanitizers.

 

[Mozart]

In my opinion, it's probably just the CO2 and other aromas from the fermentation. I know my chest freezer can put off some noxious aromas.

I also don't think such a small amount of bleach could react with anything to an extent to create much in the way of noxious fumes, though I could be wrong.

I personally would never put bleach in an airlock though. Simply put, I'd never put anything in an airlock I wouldn't want to ultimately wind up in my beer. I use StarSan myself, though I know others use cheap vodka, and other things as well.

 

[brewmeister13]

Carbon dioxide builds up in my freezer and if taking a deep breath while bent over it it definitely kicks you in the lungs. Bleach shouldn't create anything dangerous, so long as you avoided adding any other chemicals to the airlock.

One thing to note, StarSan can be reused for multiple batches. I keep 5 gallons on hand most of the time and replenish when it starts to get a few gallons low.

 

[bchurch]

I have gotten the same smell, and don't use bleach. It is the active fermentation in a closed environment. I doubt they few drops of bleach helped though. I cannot say with 100 % certainty, but I think you are fine.

 

[evrose]

@Mozart and brewmeister13.

The bleach doesn't react to form something dangerous, it IS the danger. In an enclosed space like a fridge, even a small amount of bleach could absolutely evaporate enough to form a noxious vapor pressure.

I'm not saying that's what happened here... it's hard to say, but to say that bleach and the fumes it can create isn't dangerous is just... well... wrong.

Here's an MSDS for bleach. It's not the most dangerous chemical known to man, but it's not something to be taken lightly in some environments.
http://www.sciencelab.com/msds.php?msdsId=9925000

Now, as to the question of the beer being ruined, it's really hard to say. If the fermentation was active and the resulting CO2 was pushing gas up and out of the airlock, the odds of bleach fumes getting down in to the carboy are slim. Honestly, I don't know what I'd do... the "relax and have a homebrew" in me says it's probably okay... the medical doctor in me who's treated chemical poisoning says "stay the *#*# away".

 

[Mozart]

For the record, I didn't mean to say bleach in and of itself wasn't dangerous. If it came off that way, then I chose my words poorly.

The OP asked about a reaction with bleach, and I honestly doubt it.

That said, as I mentioned before, I would never put anything in one of my airlocks that I don't ever want to see in my beer (like bleach), because sooner or later, some of it is, indeed, going to wind up there.

Best!

 

[RM-MN]

Saturday night I brewed, then placed my 6.5 gallon glass carboy in the freezer. Sunday morning I checked and found that the stopper and airlock had worked its way out, leaving the carboy open. This happens fairly often for me... no matter how carefully I dry the stopper and mouth of the carboy, it takes some time for the stopper to "set" in the carboy (tips here?).

One sure way to keep from having the stopper work its way out is not to put it in. You're fermenting in a closed freezer, no flys will get in. You can leave the carboy totally open (running naked) or cover it with a piece of saran wrap held on with a rubber band and then poke a tiny hole for the CO2 to escape.

 

[flars]

Don't worry about a couple of drops of bleach in the wort or in the freezer. That is less bleach that you would use to purify a quart of water on a backpacking trip.
When you are inserting your airlock and stopper, keep light pressure on it until movement of the stopper slows. At that point hold it from moving. It will form fit the mouth of the carboy and stay in. Unless you purchase a much to large stopper. I use the universal size for all my carboys.

 

[Shakybones]

A wet bunghole can result in some slippage.

Sorry, I couldn't resist.

 

[AlCophile]

I rarely use a bubble-lock, unless I want the sounds of brewing to soothe me to sleep. Get a few poly drying tubes from a lab supply house, and merely put water-moistened cotton in the one you are currently using, attach to nipple in bung hole with short piece of tubing.
You can hook 'em up with a manifold and use one tube for several batches. Even use CO2 from one to flush another. Ya didn't think of that, did ya?
There will always be enough CO2 coming out of batch to keep air out. (Unless you screw up). Besides, if you are going to rack, you should have some inert gas to fill headspace. There are several; not all at AirGas, either: put your think caps on!!! No, not propane.

Now, once and for all: vodka is useless. You need 70% alcohol, and even so, it will evaporate. What now?

And, the bleach-chlorine guys are right-on! Even a TINY amount plus a TINY amount of ANY acid will liberate chlorine gas. Fruit juice, beer, tomato juice will all give chlorine. They're YOUR lungs!

 

[evrose]

For the record, I didn't mean to say bleach in and of itself wasn't dangerous. If it came off that way, then I chose my words poorly.

The OP asked about a reaction with bleach, and I honestly doubt it.

That said, as I mentioned before, I would never put anything in one of my airlocks that I don't ever want to see in my beer (like bleach), because sooner or later, some of it is, indeed, going to wind up there.

Best!

No worries here. I think we're in agreement here. Cheers.