Help pinpoint off-flavor

[UnrulyGentleman]

In most, not all, of my extract brews I've noticed a fairly unpleasant (not horrible by any means) after-taste. It's always right at the back of my tongue and hard to describe: maybe metallic. A lot of times, I think it's coming from the foam/head of the beer and I can pick it up distinctly if I take a mouthful only foam. It might be due to any of the following, but I'd love to know exactly which one so I can eliminate it:

- partial boil
- quality of my water
- not sitting in the fridge long enough before tasting
- the infamous extract twang
- fermenting at a an ambient temp of around 68

I am obviously working on adjusting all of the above mentioned, but just wondered if anyone knew more precisely what it is I'm tasting. I realize it it be hard to guess without knowing full recipes and procedure, but thanks for any ideas in advance nonetheless!

 

[Lepersquatch]

Hello Rex personaly i would start with your frementing temp. I just brought two party tubs i plan to use for fermenting with some water and bottled water thats frozen. i got them at walmart for 4 bucks each.

 

[krazydave]

Here's what John palmer has to say about metallic flavors.
Not sure that this is your cause though...

Metallic flavors are usually caused by unprotected metals dissolving into the wort but can also be caused by the hydrolysis of lipids in poorly stored malts. Iron and aluminum can cause metallic flavors leaching into the wort during the boil. The small amount could be considered to be nutritional if it weren't for the bad taste. Nicks and cracks ceramic coated steel pots are a common cause as are high iron levels in well water. Stainless steel pots will not contribute any metallic flavors. Aluminum pots usually won't cause metallic flavors unless the brewing water is alkaline with a pH level greater than 9. Shiny new aluminum pots will sometimes turn black when boiling water due to chlorine and carbonates in the water.

The protective (grayish) oxides of aluminum can be enhanced by heating the clean pot in a dry oven at 250°F for about 6 hours.


More info here:
http://www.howtobrew.com/section4/chapter21-2.html

 

[KevinW]

I was having a similar issue with some of my beers when I read about other brewers having problems with Willamette hops!

I don't know why but Willamette was giving me that barely perceptible metallic taste. I also noticed a kind of "dirt" flavor too.

I stopped using Willamette and have been fine ever since!

I am not bad mouthing Willamette by any means they just don't work for me!

Just throwing it out there!

 

[UnrulyGentleman]

Interesting stuff, thanks for the info guys. I agree that my temps need to be controlled. Weird that this flavor is only on the back and not on the front, though.

 

[william_shakes_beer]

Why don't you post a sample an we can all give it a taste