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Is an infected beer infectious?

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djonesax

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Say a beer got something bad in it that caused some off flavors. Could hooking that up to kegerator with a shared CO2 manifold, possibly infect other beers already fermented?

David
 
Yes. It does depend on how the flow goes, but yes.

I'm aware of one setup where there was catastrophic failure and the beer went up the airline and got the manifold gunked up with beer. If it had been infected beer, it would have infected the line. I think the guys just cleaned it cause it was dirty, not infected.
 
Yes. It does depend on how the flow goes, but yes.

I'm aware of one setup where there was catastrophic failure and the beer went up the airline and got the manifold gunked up with beer. If it had been infected beer, it would have infected the line. I think the guys just cleaned it cause it was dirty, not infected.

But can it infect through the gas line even if the line is clean?

Thanks,

David
 
As long as no beer entered the gas line, you should be okay. Unless you did something funky (no pun intended), your gas line should always be pushing out relative to the beer. However, if beer got up into the gas line or you are otherwise concerned, take it apart and clean with hot PBW and give a starsan soak. Or buy new hose.
 
As long as no beer entered the gas line, you should be okay. Unless you did something funky (no pun intended), your gas line should always be pushing out relative to the beer. However, if beer got up into the gas line or you are otherwise concerned, take it apart and clean with hot PBW and give a starsan soak. Or buy new hose.


I have a beer that tastes a little tart and I am not sure if it was a temperature thing or an infection. I force carbed by connecting the gas to the out connector and got a little beer in the lines but not as far up as the manifold. I took them apart, rinsed, starsan'd and reassembled but I was wondering if it could infect the other beer through the open CO2 lines regardless of if actual beer made it through the lines to the other kegs.

David
 
The short answer to this question is "not really". beer spoilage is almost always wort spoilage, meaning something went wrong at the beginning of fermentation and an undesirable organism amplified up along with, or often instead of, the desired yeast strain.

These undesirables are mostly temperature dependent, the same way that ale yeast is. Since 99% of homebrew ferments in the 65-75 deg F range, this is a good environment for these bugs to thrive. However, once you crash the temp down to storage/serving temps (high 30s - low 50s?), these organisms mostly go to sleep. So even if you had a badly contaminated* keg hooked up to a multi-keg CO2 manifold, it's not really a big deal because assumedly this whole contraption is sitting in the cold box so the bad bugs can't multiply rapidly. At the very least, the kegs themselves are sitting cold, so if somehow beer from the contaminated* keg made its way to another keg, it wouldn't grow up in the second keg. it wouldn't do that beer any good, but it wouldn't do it much harm either.

now, if you're still freaked out about this in terms of your CO2 manifold, then my next question is: do you have backflow preventers between your regulators and your kegs??

if you don't, you really need them! even HBers with just a one-keg setup need this! the main reason is to keep beer from shooting back into the valve body of the regulator, drying on all the inner surfaces of the mechanism, and just generally screwing up the works. if you have laid out the money for, and are into this hobby enough to own a CO2 manifold, then you should definitely have backflow preventers for every keg line! they're like $4-5 each, but how much were your regs? $50? $75? and how much is it worth to never have to worry about whether your reg is showing the correct psi? if your regs have never seen a corny without a blackflow in between, then you'll probably never have a reg problem.

*Contamination vs. Infection: An "infection" is what we call it when an invading microorganism colonizes a living thing. Since beer is not a living thing, it cannot become "infected". Instead, we say that it is "contaminated". Conversely, when you get sick, catch a cold etc, you wouldn't say that you're "contaminated". Nobody ever heard their girlfriend complain about a Urinary Tract Contamination, ha ha.

The more technical distinction that's being made here is that invading microbes that infect do so by entering "inside" of an organism. Microbes that contaminate beer can't really be "inside of" the beer, because beer doesn't constitute a larger macrosystem. The microbes are just "around" and "between" the beer particles, feeding on them.

(Source: I'm an ex pro-brewer with a chemistry degree)
 
Wow great post, thanks. Can you suggest a back-flow preventer? I found some for 12 bucks, but didn't see any for 5 bucks.

David
 
I made an English Mild a few months back, and bottled it on 06/13/2014. Up until a month ago, it tasted great. It recently started to taste "off" but it wasn't a bad kind of off. It is developing a very sour flavor that I have no idea where it came from. I am not really a sour beer kind of guy, but it might be interesting in a couple of more months. This is the first "bad" batch of beer in two plus years, so I am baffled to how it could have happened. Maybe I do know actually... my Zapap tun had not come apart for quite while (months), so I rinsed and rinsed, flushed, bleached, flushed again, and forgot about it. At least I thought I did. I finally took it apart, and I am sure it is clean now. I guess I will know 4 months after I bottle the next batch.
 
They're called check valves and are generally sold as such. Many regulators and manifolds come with them pre-installed, usually built into or connected to the shutoff valves.

This is the first I've ever heard anyone dispute the term "infected" when talking about beer with bacteria in it. That term is used extensively in the brewing community. *shrug*
 
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