Infection in kegs and spreading? It was the gas lines!

So after reading that previous thread about diacetyl forming after packaging, I’m starting to reassess the issues I have. My issues are most noticeable, I think, in hoppy beers. Amber and darker beers either cover it up or it isn’t there. But with hoppy beers, the flavor starts out nice and begins to change after about a week in the keg. The hop flavor goes away and it takes on this flavor that tends to make all my hoppy beers eventually taste the same, or very similar. Some beers have gotten super buttery/butterscotchy.

My question is, can a dirty dip tube in a keg spread and eventually infect the whole keg? My guess is, yes, it can. Also, can dirty tap lines spread back down into the beer and infect that?
Many of these beers taste great when I tap them, but after a few days start to turn south…it’s very odd and quite frustrating.

I’ve never run a dip tube brush through my dip tubes, so this is why I’m wondering about this. I run either beer line cleaner or pbw through the lines after a keg kicks, rinse with water, then run starsan through. But in looking through one of my dip tubes, holding it up to a light, I noticed what looked like dirt or crud in there. So it got me wondering…

Two things come to mind leading to these diacetyl issues: oxidation of acetolactate compounds which produces diacetyl (seems unlikely, but possible, I suppose) and pedio infection from dirty dip tube/lines.

Any insights?

Thanks,

Jesse

Nobody, huh? Bummer…

if the dip tube was dirty, it could certainly spread throughout the keg. i dont think the beer lines would be able to go back into the keg… but i could be wrong.

maybe in your CO2 lines there’s some build up. one time beer go forced through my co2 lines and i had to replace them. the lines got gross, and all the co2 running into my other batches flowed past gross/old beer buildup. maybe that’s happening?

I read your post earlier, 10 mins ago I poured a glass of a single hopped bitter (Columbus). About half a keg left of a great beer. Now I’m getting a solvent taste, almost mouth-numbing.
You’ve got me thinking that my cleaning hasn’t been enough. Initial fermentation was at 65* actual temp with Wy1028. I hope it’s from the keg, since I
have a black ale (CDA :wink: ) on the yeast cake right now.

If you have a dirty storage container and you put tonight’s dinner leftovers in it, will the whole pot roast be contaminated or just the side that is near the dirt?

Eventually the whole thing will be bad. Beer, because it is liquid, I feel the whole thing will be bad within minutes/hours. A roast or brick of cheese, can be somewhat salvaged.

But I’ve never had only a portion of a container of chicken be good and another portion be bad.

In a situation like that, I would be tempted to start cleaning. I clean my beer lines after every 2-3 kegs anymore, since it is so simple. As to CO2 lines I have not discovered issues, but I soak the Gray QD’s in the same PBW or BLC, then rinse and sanitize. As you use these kegs up, I would completely disassemble them for a thorough cleaning and sanitizing and do the lines again at that point, along with the taps. Keep a bottle of spray star San solution handy at all times and spray anytime you disconnect or connect anything in the system. I see what can grow in a fridge, so I try my best to stay ahead of it by spraying liberally.

Good luck. I hope it turns out ok for you.

:cheers:

[quote=“S.Scoggin”]maybe in your CO2 lines there’s some build up. one time beer go forced through my co2 lines and i had to replace them. the lines got gross, and all the co2 running into my other batches flowed past gross/old beer buildup.[/quote]This happened to me a couple years ago. I had 6 kegs go bad, they all tasted great at kegging but were nasty after a month or so. I force carb kegs in my basement and the light isn’t very good so I didn’t notice the mold in the gas lines. I redid all my gas lines and disconnect so they can be taken apart and cleaned.

Interesting, thanks for the input, guys. I think what I may do is seize kegging any more beers until the 2 I have on run out, then reassess the situation and do some cleaning and replacing of things. I’ve been doing more bottling lately anyway, less moving parts, more variety (for me).
I will try to post back any results or thoughts (if anyone cares).

It is interesting though that I don’t seem to have any issues with beers that aren’t hoppy. It’s probably happening to those non-hoppy beers, but when hops are in the forefront, I think it’s easier to notice something is up if it starts to taste weird. Dark beers have all the roasted malt to cover up things like diacetyl. My bottled beers seem great, although I haven’t bottled an IPA, so that’s next on my list to see if it really is something up with my kegging system or my fermentation practices.

Cheers & beers.

Sounds like its time for a Sanitation Stand-Down.

Yeah it is, I plan to run the kegs out I have on and give them a thorough soak. Although one of the kegs is a new keg, and that one doesn’t seem to have any issues, so perhaps I should put an IPA in there to see how that goes. The beer in that one is the first to go in that one; it’s a 3 gallon keg that I cleaned well before using.

Sure ruins a lot of beer trying to figure this sh*t out, but I’ll get it.

[quote=“ynotbrusum”]In a situation like that, I would be tempted to start cleaning. I clean my beer lines after every 2-3 kegs anymore, since it is so simple. As to CO2 lines I have not discovered issues, but I soak the Gray QD’s in the same PBW or BLC, then rinse and sanitize. As you use these kegs up, I would completely disassemble them for a thorough cleaning and sanitizing and do the lines again at that point, along with the taps. Keep a bottle of spray star San solution handy at all times and spray anytime you disconnect or connect anything in the system. I see what can grow in a fridge, so I try my best to stay ahead of it by spraying liberally.

Good luck. I hope it turns out ok for you.

:cheers: [/quote]

New to kegging myself, the suggestion to immerse the disconnects in PBW then star san is something I probably wouldn’t have thought of but makes perfect sense.

Is there a reason to use BLC or one of the ‘line cleaners’ as opposed to PBW?

It’s an acid cleaner, which gets rid of more beer stone than PBW. I don’t use it every time, but try to every couple kegs. It’s kind of pricey…
It really would be interesting to know that a dirty quick disconnect could spread back down into the dip tube and infect the whole keg. I’ve tried tasting beers with a picnic tap and the beer tastes the same, so I know it can’t be pedio in the lines. Unless it can spread back down into the keg…

I identified the diptube as the source of a recurring off-flavor by noticing that the first pour of the night tasted worse than the second and then pulled the tube and could see the crud just like you. What I now do is to pull the beer tube out and then drop loose into the keg (makes a great stir-rod for dissolving the PBW), then hitting it with the diptube brush before and again after the keg is done soaking. Haven’t had the problem since.

+1, get a diptube brush. They are so cheap that there is no excuse not to have one.

I did get a dip tube brush just yesterday. It didn’t seem to get the stuff out. I’m soaking one of my kegs and plan to soak my others before I do anymore kegging. I’ll be bottling for a while and kegging in my new keg that shouldn’t have these issues since it’s currently housing its first beer.

It probably is overkill, but I break down the keg completely after each use. I don’t always do a full wash - just a hot water rinse if the keg went quickly, but a deep clean when necessary, and a good sanitation either way. I also store empty kegs with CO2 head pressure and purge out oxygen to a large degree.

:cheers:

I have a pump-based keg cleaner with a bucket heater I made. I pump 150F PBW through the disconnects and a spray ball that almost reaches the top of the inverted keg. I follow that with a 150F hot water rinse via the same (cleared) washer. It’s probably time for me to do keg break-downs to check dip tubes and poppets for gunk. Now that I’m up to 36 kegs, I’ve decided that I should identify each keg and record their deep-clean/field strip events. That way, if I suspect a sanitation issue, I may be able to isolate the culprit keg.

[quote=“ynotbrusum”]It probably is overkill, but I break down the keg completely after each use. I don’t always do a full wash - just a hot water rinse if the keg went quickly, but a deep clean when necessary, and a good sanitation either way. I also store empty kegs with CO2 head pressure and purge out oxygen to a large degree.

:cheers: [/quote]
I do as well. All removeable hardware (poppets, dip tubes, etc) get soaked in Oxyclean. The liquid dip tube gets hit with the brush. Then I’ll assemble, add more Oxyclean and hot water, pressurize the lid and let soak for 30 minutes or so. Rinse well, hit with star san. Never had an issue with clean beer getting infected in the keg.

I take my kegs apart and clean and sanitize all the bits nearly every time. The only time I don’t is if it’s a beer that’s going to be drank quickly like for a party, then it’s just a rinse with hot water.

I soaked a couple dip tubes that looked to have gunk in them for a day, then I ran a dip tube brush through and it looks like there still something in there. Is it possible for there to be corrosion in the dip tubes? And if so, would this be a culprit? Grasping at air here…

Pretty soon, I’m going to run an experiment. I’m going to make a simple hoppy pale ale, split it between a brand new 3 gallon keg I have and one of my other kegs and see if both remain stable or what happens to each. Then I can see if it’s a fermentation issue (which I doubt, but ya never know) or a sanitation issue.
Time to ruin some beer!