most common off-flavors

Having read this article https://www.homebrewersassociation.org/how-to-brew/5-common-homebrew-flavors-fix/, plus its follow-up, I was wondering, dear judges, what the really really truly most common off-flavors are that you encounter in beers? Are there three or so flavors that stick out?

Really surprised diacetyl wasn’t on that list. That is one of the most common flavors I come across in home and commercial beers.

There’s a second article with 5 more off-flavors: 5 More Beer Off-Flavors and How to Fix Them - American Homebrewers Association

Big ones in approximate order of how often they seem to occur (with my own definitions of flavor descriptors):

  1. DMS (creamed corn, cabbage, celery, rotten vegetables)
  2. Hot alcohol / solvent (bad vodka)
  3. Oxidation (wet cardboard & sadness)
  4. Diacetyl (butter or butterscotch or slickness)
  5. Extract twang (metallic caramel & hint of banana)

I’m somewhat sensitive to DMS, so I might pick on it more than it is perceived by others.  I don’t usually pick it up in my own beers.  I think it’s due to less than adequate boil rigor primarily, and I boil every batch super vigorously.

Solvent flavors basically come from fermenting too hot.  Keep it cool, eh?!

There are different forms of oxidation, but the stale form will happen to any/every beer with enough age, so it’s always a possibility.

The other stuff really doesn’t happen as much anymore in my experience.  Even diacetyl isn’t as prevalent as much anymore, and extract twang is less and less prevalent, at least with brewers who’ve got a couple years experience and know to use fresh dry extract.

By the way… a personal peeve of mine… astringency is WAY less prevalent than most judges will tell you.  I would say that 3 times out of 4 that a judge uses the term “slight astringency”, they are in fact full of crap, trying to show off their judging prowess or something.  This occurs greatly with inexperienced judges but unfortunately often continues farther up the ranks.  While astringency is indeed very possible, I’ve experienced it many times, the term is WAY overused.  People describe it like a bitterness in the flavor.  I’ve even seen a Master judge use the term when describing the aroma!  Totally, totally wrong.  It’s a dryness, as if you’re sucking on a sponge or have been mouth-breathing in the Mojave Desert.  Can best be duplicated by chewing a while on grape skins, after the juice is all gone, just keep chewing on those skins.  That dryness, which is also a sort of spiciness, is astringency, and it’s usually caused either by pH problems or by wild critters.  It’s not the same as bitterness.  Be cognizant of this common error.

I don’t know why but very often when I drink relatively low quality homebrews, I  taste astringency and some phenolic off-flavors that I can’t describe very accurately.

You can sense astringency, but you cannot smell, see, or taste it.

I find astringent things make my teeth feel weird, for lack of a better way of putting it. I also notice astringency as a kinda tongue prickling sensation. Think a really tannic wine. Actually that’s what I don’t much care for wine.

I’ve yet to ever notice astringency in beer. I’m sure it can happen, but I think you’d have to really abuse your malt to get it.

I tend to be sensitive to some things that may or may not be “off flavors”.  Sherry/Dark dry fruit I run into a lot, which can be good or bad depending on the style.  Imperial Stout - Good! IPA - very bad! My BJCP exams have said that I am sensitive to oxidation, so that dark dry fruit is always a warning to me, but I try really hard to not knock it as oxidation unless I pick up the wet cardboard/paper as well.

I tend to run into grassy a lot too, which usually comes from dry hopping, and even in IPAs is usually not wanted, but sometimes it’s not too awful.

If I did a list like DM, I might put diacetyl up at the top.  I encounter it at bars that are increasing their taps to include non-hoppy craft beers.  While diacetyl might not be the most common one, when I encounter it, it often is spectacularly bad.

Phenolics is probably 4th.  Usually subtle.

Oxidation is probably fairly prevalent as lack of freshness.  It seems that many people enter bottles filled from a keg into homebrew competitions, and the result seems to be muted flavors rather than off flavors.

True true. Some kind of harsh bitterness then, not astringency then.

I thought of another good example of what I think astringency is: those little nasty bits from the hull of a pecan.

Yes! That captures it perfectly. It’s a feeling, not a taste.

Top 5 for me in no particular order
Acetic Acid vingary
Light Struck skunky
Oxidation wet cardboard
Diacetyl movie theater popcorn
Assorted contamination such as clorine chlorophenol, isovaleric acid stinky foot, ? musty dish water

This is what I run into most often, in no particular order

Sulphury
Phenolic
Paper/cardboard oxidation
Diacetyl
Solventy
DMS
Acidic
Grassy
Estery(too much for the style)

[EDIT - mouthfeel]
Astringent mouthfeel (not flavor nor aroma)
Hot alcohol
over/under carbonation

I think acetaldehyde is one. Poorly fermented beer has an underlying vegetal flavor of raw pumpkin or melon-rind.

Dankness is probably the most common off-flavor I find in home and craft brew, but usually that is the result of some chucklehead using too much CTZ hops.  ;D

What, no juicy?

I kid.

I know what you mean. I do think it borders on astringency. It’s like a combination too-high ph in the mash, too much high-alpha acid hops early in the boil without the body to back it up and bad sanitation at bottling. I’ve noticed it repeatedly in homebrews that have been given to me over the years (a couple times in my own to a lesser extent, so I believe). Very strange.

I remember first experiencing this phenomenon a number of years ago when a variety pack was given to me by an “award-winning” homebrewer. I couldn’t drink any of them. It was then that I decided that I would never enter a competition.

Interesting. How do you know that’s one of the problems?

Purely a speculative example. I could’ve just stopped at “bad sanitation”.