I am having problems identifying off flavors iny beer

I read a few explanations as to what could be causing off flavors in beer and I think it is most closely associated with the "bitter tea bag" taste. I have been monitoring the mash temp so I don't think it is from that, and as far as I can tell none of the crud that clings to the side has been finding its way into the beer.

Anyone have any ideas as to what might be causing this? I noticed my fermentation temp (71-73 degrees) is a little higher than most recommended temps, but this flavor isn't associated with the temperature from what I have read. I think it might also be worth mentioning that the flavor does not appear once the beer has been bottled for at least 3 months or so (at least not with a porter I brewed). It doesn't really taste like the flavors described as a cause of acetaldehyde, so I am not sure if it is from that either since I take gravity readings (which are in the FG range) to confirm a stop in fermentation.

Basically I have no idea as to what it could be and am hoping someone might be able to point something out that I may not know about. Anyone have any thoughts on this?

"Bitter tea bag taste" is probably astringency (tannins).

It is probably related to pH, most likely in the sparge.

Yooper said:

"Bitter tea bag taste" is probably astringency (tannins).

It is probably related to pH, most likely in the sparge.

Click to expand...

Thank yooper.

Could you maybe explain a little more for me as I'm still learning. I'm not sure exactly what my water pH is, but I remember I tested it once since I use an aluminum pot and from what I gathered it was in the "safe zone", for lack of a better term. I just use SF tap water, if anyone has the info on the water here. I'll post the numbers I got once I get back home.

How hot is too hot when sparging? I just use warm tap water

Han_Solo said:

Thank yooper.

Could you maybe explain a little more for me as I'm still learning. I'm not sure exactly what my water pH is, but I remember I tested it once since I use an aluminum pot and from what I gathered it was in the "safe zone", for lack of a better term. I just use SF tap water, if anyone has the info on the water here. I'll post the numbers I got once I get back home.

How hot is too hot when sparging? I just use warm tap water

Click to expand...

The water pH really doesn't matter. What does matter is the mash pH, and then the pH of the sparge. Generally, you want the pH under 6 for the sparge. I've found that my alkalinity is a bit too high in my water, so I use reverse osmosis water for the sparge. If you're batch sparging, the pH issues don't seem to be as great as for fly sparging.

Han, you need to check out the water chemistry primer in the brewing science forum. Water chemistry is that "final frontier" of home brewing. I've been much happier with my brews since I started understanding chemistry.

Yooper, as a Bears fan your avatar has been pretty difficult for me to look at. Sorry about Monday.

+1 on checking your water pH.

A less likely, but possible, candidate could be recipe design (e.g. too much roasted barley or black patent malt in your porter).