Author Topic: Off Flavor Two Weeks After Kegging  (Read 4368 times)

Offline CB-Illinois

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Off Flavor Two Weeks After Kegging
« on: February 15, 2012, 10:07:17 am »
Hi all,

I have a question about keg/bottle conditioning beer.  I made a close of Bell's Double Cream Stout and it tasted GREAT after secondary fermentation, and even after bottle conditioning for a week (although it was a little flat).  The next week the beer developed an off flavor a little like vinigar.  I have noticed this quite often when tasting other's homebrewed beer as well.

Any ideas what might have happened / how to fix the process os that this no longer occurs?

Thanks!

Offline Hokerer

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Re: Off Flavor Two Weeks After Kegging
« Reply #1 on: February 15, 2012, 10:12:18 am »
Hi all,

I have a question about keg/bottle conditioning beer.  I made a close of Bell's Double Cream Stout and it tasted GREAT after secondary fermentation, and even after bottle conditioning for a week (although it was a little flat).  The next week the beer developed an off flavor a little like vinigar.  I have noticed this quite often when tasting other's homebrewed beer as well.

Any ideas what might have happened / how to fix the process os that this no longer occurs?

Thanks!

"Vinegar" sounds like maybe you've got an infection somewhere.  How good is your sanitation?  and how do you go about it?
Joe

Offline motochriso

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Re: Off Flavor Two Weeks After Kegging
« Reply #2 on: February 15, 2012, 11:00:46 am »
I had this same problem >:(…. Stuff would go into the keg tasting great and within a week or so would taste sour.  Solution:  Hot water PBW, Sani-clean then  Star-san everything.  Things turned right around after that.  I now clean thoroughly then ½ fill the keg with sanitizer, shake for a few minutes seal it up and turn it over and let sit for an hour.  Make sure to also clean and sanitize all ports and those hard to reach places, the welds and tight spaces near the tops of kegs can easily hide bacteria.    
« Last Edit: February 15, 2012, 11:04:51 am by motochriso »
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Offline hopfenundmalz

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Re: Off Flavor Two Weeks After Kegging
« Reply #3 on: February 15, 2012, 11:52:23 am »
Some in the club have fixed stubborn infection in the keg systems by taking the posts off and boiling those.  I have done this too. 

You can also replace all of the rubber parts.  A long brush to clean out the beer dip tube is a good thing to have when doing the cleaning.

Does your beer taste like this for the first pour only?  If that is the case you could have an infected line or tap.
Jeff Rankert
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Ann Arbor Brewers Guild
Home-brewing, not just a hobby, it is a lifestyle!

Offline euge

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Re: Off Flavor Two Weeks After Kegging
« Reply #4 on: February 15, 2012, 12:05:34 pm »
You also might consider replacing your racking and transferring hoses.
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Offline thomasbarnes

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Re: Off Flavor Two Weeks After Kegging
« Reply #5 on: February 15, 2012, 04:50:16 pm »
Definitely consider cleaning or changing your hoses first. They can easily get scratched and can be hard to clean. Many homebrewers replace their hoses on a 6-12 month schedule. It's cheap insurance.

Also, when you say "a little like vinegar" does that mean that the off-characteristic is detectable in the aroma AND flavor, but is at a low level, or that it's only detectable in the flavor and is sour, but doesn't taste exactly like vinegar?

If you're getting a sourness that is easily detectable in the aroma and the flavor, and which smells and tastes like vinegar, it's very likely to be an acetobacter infection and the off flavor/aroma is acetic acid - which is the active ingredient in vinegar. Since acetobacter is aerobic, it's an indication that air is getting into your keg and/or lines. So, in addition to replacing your hoses and sanitizing the bejeezus out of your equipment, also look for loose connections or poor seals where air might be getting in. That might also account for the fact that you're losing carbonation.

If you're getting a sourness which is hard to pick up in the aroma, but which is more detectable in the flavor, with a "crisper" less lingering sourness, reminiscent of yogurt, then you've got a lactobacillus infection and the sourness in your beer is lactic acid. Unless you're using old dairy equipment in your brewhouse, or are also making cheese or yogurt using the same equipment, the most common source of lacto bugs in beer is the human body, especially the human mouth. In any case, the solution is obvious - don't do it!

If you must touch your cooling wort or fermenting beer with your hands, you'll need to scrub your hands and sanitize them as if you were prepping for surgery. That means scrubbing from fingers to elbows with a scrub brush and surgical soap, paying special attention to the areas under and around the fingernails, for at least 5 minutes.

Another bad habit which can result in lacto infections is starting siphon hoses using your mouth. Even if you gargle with vodka or mouthwash, you'll need at least 2 minutes of contact time to sanitize your mouth, and even then you probably won't kill all the bugs. Use an autosiphon instead; not only is it much more sanitary, it's also a real time saver.