Why do good beers sometimes taste bad on tap?

[Kalmah]

I couldn't find a post on this so I thought I'd start one.

Occasionally I will order a fairly prolific go to craft beer I know and like on tap and I am unexpectedly disappointed. It might have off favors or be completely dead and flat with no head. This is usually at bars/restaurants that don't have a huge selection of craft beers. I originally thought maybe I was the first to order that beer in a few days and I got most of the beer that was sitting in the tubing, but that should only account for a few ounces. Any thought on what they are doing wrong?

 

[Teromous]

Bad lines can ruin every beer that passes through them; not just the first few ounces. It could be an old keg that the bar is just sitting on until it runs out. It could also be that the bar isn't setting the CO2 pressure correctly. Maybe the bar tenders are cleaning out the taps with dirty rags. I've seen all kinds of crazy stuff.

Additionally some beers just taste better in bottles. I constantly hear people say that they prefer the flavor of bottle conditioned beers over kegs. This would only really be the case if it's bad on tap everywhere you go.

 

[thelastleroy]

Having worked in a pub for a few years in high school, I would suggest that the beer you ordered wasn't popular enough at the bar to keep the lines moving. Your idea about the draft lines is a reality; consider many bars/restaurants have the beer fridge in the basement. The lines have a long way to go!

A very popular BMC beer will keep flowing all day and night, every night, and most off-flavors due to draft line hygene will be negated. The lines on your craft brew are probably always full of warm, stationary beer. Even more concerning is the idea that some bar owners don't clean their draft lines often enough, or only when the keg kicks etc....

Get your craft beer where it's fresh, and popular . Drink bulk production at the pub. At least you know what you're getting!

 

[Cyclman]

Just like at home, it is a PITA to clean draft lines. Some bars don't do it. I know that (at least years ago) macros cleaned the lines for the bars, to maintain consistency.

 

[Brettomomyces]

Then there's also handling abuse as well, not every keg gets to sit in a nice refrigerated environment its whole life. And some may be way past their prime and just haven't sold quickly enough.

 

[Sailingeric]

I suspect dirty lines. I was a small sports bar by my house, not the fanciest of places where you could tell that cleaning the lines regularly was not part of the plan and of the 3 beers I had they all had a bit of diacetyl taste to them.