Where did we go wrong?

[warriorpoet85]

Hey guys,

Have to toss a batch of beer and after my neighbor and I put a ton of work into this Octoberfest, I want to learn from the experience.

Typical Marzen. Actually it was Bier Muncher's Octoberfast (only change was using Nottingham yeast). Everything during the boiling process and fermentation seemed to go great. Hit our original gravity and final gravity smack dead on. 72% brew house efficiency. Tasted WONDERFUL coming out of the fermenter into the keg (We force carb). Standard cleaning process to the keg (oxy clean soak for a couple of days followed by 6-7 wash outs to where oxy clean can no longer be tasted). Oxyclean soak for two days. Rack to keg the next day. Tastes at one week after tastes great, still carbonating. Taste at two weeks still good. Taste at three weeks and all of a sudden it tastes like a mix between SOUR APPLE and STAR SAN. Changed the line out with a completely new line and it tasted exactly the same.

Yes I sanitized the keg and the lines as described above.

My questions:
(1) Why does a beer taste so good at one and two weeks during force carbing (And directly out of the fermenter) and then turn into this terrible (and unservable) off taste after two and a half weeks?
(2) What are typical causes that lead to these off tastes? If it's an infection of the batch is there something wrong with the way I sanitize?

Thanks for any and all help!

Warriorpoet85

 

[warriorpoet85]

The second soak i mentioned is with star San. Just a typo.

 

[jbguzzi]

That is odd. I use pbw first and a star san rinse. I have filled kegs on star san foam and had no issues. You clean all the ball lock connectors? You can take them apart, you probably know that.. Sounds like to much AA . Maybe let it condition for a week or two.

 

[Surly]

IMHO, people use the word, "infection" too soon.

From what you say, you should be fine. Go back and in your own mind confirm what you have said above.

If you are using clean equipment and you have sanitized everything you should be fine.

You said you hit your numbers. I assume your recipe was properly weighed in, therefore, don't dump this batch yet.

Finish it and let it sit for a bit. Then, in six months make your final decision.

 

[warriorpoet85]

I am still wondering why it tasted so good out of the fermenter and in the keg conditioning for a week or so before becoming sour? If it were just green wouldn't it taste like that from the get go?

 

[adiochiro3]

I have the same problem with a Dopplebock. when I bottled it, it was really good -- after a 6 month lager. I boiled priming sugar and mixed it in with champagne yeast to ensure good carbing. Six weeks later, it tasted a bit sour -- and still does. I used the same technique for a Wee Heavy, done at the same time, and it tastes flipping fantastic. A real puzzler.

 

[savannahbrew]

How much had you drank out of the keg? I have had similar experiences (not the same taste per se) towards the bottom of the keg i have had a beer change flavors very quickly. I am not referring to the last two or three pints either. I am curious to hear others responses!

 

[jbguzzi]

There are services where you can send the brew and have it analyzed. Maybe that can yield a clue. I think white lab dies it.

 

[shaigl]

what happens in commercial beers is: once you started drinking a kag you have a certain period of time, depending on the beer itself, that you have to finish it before it will go bad.
that time period can go from 3 days to couple of weeks, again, depending on the beer and its type. (i dont know which type holds for how long).

im guessing it depends on how much you drank from the keg and all that. personnaly i use bottles

 

[chickypad]

what happens in commercial beers is: once you started drinking a kag you have a certain period of time, depending on the beer itself, that you have to finish it before it will go bad.
that time period can go from 3 days to couple of weeks, again, depending on the beer and its type. (i dont know which type holds for how long).

You seem to be talking about a keg which you pump with air to dispense. Dispensing with CO2 is completely different. Of course flavor can change, for example loss of hop aroma, but a keg dispensed with CO2 will last indefinitely and should not go "bad".

edit: little slow, beat me to it

 

[eltorrente]

what happens in commercial beers is: once you started drinking a kag you have a certain period of time, depending on the beer itself, that you have to finish it before it will go bad.
that time period can go from 3 days to couple of weeks, again, depending on the beer and its type. (i dont know which type holds for how long).

im guessing it depends on how much you drank from the keg and all that. personnaly i use bottles

That's only true because of the airpumps commonly used in commercial kegs, like for parties. If you use CO2, oxygenation isn't an issue, and kegs don't go bad.

 

[warriorpoet85]

It's primed with co2. Only took a sip twice (once each week) to see how it was coming along. Plan was to serve it for a neighborhood octoberfest. Definitely cannot serve it now. First time in probably 10-15 batches this has happened.

 

[Jaybird]

Are you doing just a "taste" at 2 weeks or are you "drinking" at 2 weeks. If just small "tastes" It sounds like you have gotten into the yeast and trub that has dropped out of suspension maybe. Pull a couple of pints and toss em out and see if that clears up the taste. I have had this happen in the past and I was just tasting a bunch of crap that was dropping out. Just a thought anyway.

Cheers
Jay

 

[IslandLizard]

That is odd. I use pbw first and a star san rinse. I have filled kegs on star san foam and had no issues. You clean all the ball lock connectors? You can take them apart, you probably know that.. Sounds like to much AA . Maybe let it condition for a week or two.

^+1

Could also be the keg. Did you disassemble the posts and scrub and sanitize the inside of the diptubes as well as the poppets, posts, etc.? Nasties can hide in there.

Did you just get your gas cylinder [EDIT] swapped? There have been incidental reports on tainted gas. Smell it, but don't blow it directly in your face though.

 

[warriorpoet85]

I did change all of the fittings, etc. I don't even know how to scrub the inside of a dip tube? What could fit inside that and provide adequate length too?

I did just change my CO2 tank actually. I'll have to smell it when I get home.

I wasted several pints, changed out my dispensing line and that didn't make a difference. Still tasted like sour badness.

 

[eltorrente]

One that really helps when cleaning the kegs, is to have an out connecter attached when soaking it. This makes sure the diptube gets fully soaked in cleaner/sanitzer when soaking. If you don't attach one, you can get a dip tube that has a dry airpocket.

I always just soak my keg in EasyClean for about an hour or two after use, then star san. I have both connecters attached during soaking, so the liquid will get inside the valves and dip tube(s).

 

[IslandLizard]

^+1
Pushing cleaning liquid (and Starsan later) through the keg with some CO2 helps to get all areas soaked in cleaner and sanitized. There are thin long dip tube/hose brushes just for the job. In a pinch you could tie a piece of string to both ends of a thin brush or a wad of fabric and pull it back and forth a few times with some PBW. In general it shouldn't be necessary, but maybe something tenacious built up or got stuck inside. In one of my saisons I found a few small black oily deposits in my carboy (mostly around the krausen ring) and later in my keg. Fermentation byproducts perhaps? I forgot to inspect them under a microscope, but washed everything out really well.

When you swap out your CO2 tank a previous user may have had some backflow that got in the tank and is festering. Or a contamination got picked up during filling. The odds are small, but it has occurred. There is at least one report of this on the board. And someone else had persistent infections in his kegs, that he could not eliminate, no matter how well he scrubbed, cleaned, sanitized and inspected. No-one ever considered the gas as a possible culprit. Again a small chance.

 

[shaigl]

That's only true because of the airpumps commonly used in commercial kegs, like for parties. If you use CO2, oxygenation isn't an issue, and kegs don't go bad.

fair enough