Slight Sour taste in bottled brews - is it a mash pH issue?

[mikeburns]

Hi there everyone, long time lurker on this board, finally decided to join up and maybe be a part of the forum!

At any rate I have a minor problem that I would love to troubleshoot with you.

I currently BIAB and have dramatically improved my beers with fermentation temp control and recently water adjustments. I am now starting to focus on the small off flavours in a bid to improve the last 10 percent or so.

Since altering mash pH (calculated only, using EZ water calculator, not measuring exact pH with a meter) using acidulated malt, my beer has drastically reduced its astringency and is now much cleaner and more drinkable. But with this I have noticed a slight sourness in the aftertaste of the beer. By slight I mean very marginal, certainly not sour like I envision a bacterial infection to produce, so I do not believe it is an infection. What I am wondering is if I perhaps have overshot my pH calculations and gotten too low of a pH? I calculate my pH to 5.4. If this has somehow dropped to 5.3 or 5.2 would that be low enough to lead to a slightly sour aftertaste in the finished beer?

I am careful with sanitisation and cleaning, using starsan carefully. Fermentation is controlled at 18 degrees C and have noticed the flavour with both US-05 and S-04 dry yeasts. Can taste this off flavour in both my recently brewed Janets Brown Ale, Epic Pale Ale Clone and my recent session IPA. All three of these beers I calculated the mash pH to 5.4, but haven't been able to check for sure due to not owning a pH meter.

My next beer I brew I will aim for 5.5 mash pH and see if that improves the off flavour.

If anyone has any thoughts on this I would love to hear it!

 

[didinho]

If anyone has any thoughts on this I would love to hear it!

did you measure the finished beer ph?
from 3.8 to 4.8 should be normal.

 

[RM-MN]

Hi there everyone, long time lurker on this board, finally decided to join up and maybe be a part of the forum!

At any rate I have a minor problem that I would love to troubleshoot with you.

I currently BIAB and have dramatically improved my beers with fermentation temp control and recently water adjustments. I am now starting to focus on the small off flavours in a bid to improve the last 10 percent or so.

Since altering mash pH (calculated only, using EZ water calculator, not measuring exact pH with a meter) using acidulated malt, my beer has drastically reduced its astringency and is now much cleaner and more drinkable. But with this I have noticed a slight sourness in the aftertaste of the beer. By slight I mean very marginal, certainly not sour like I envision a bacterial infection to produce, so I do not believe it is an infection. What I am wondering is if I perhaps have overshot my pH calculations and gotten too low of a pH? I calculate my pH to 5.4. If this has somehow dropped to 5.3 or 5.2 would that be low enough to lead to a slightly sour aftertaste in the finished beer?

I am careful with sanitisation and cleaning, using starsan carefully. Fermentation is controlled at 18 degrees C and have noticed the flavour with both US-05 and S-04 dry yeasts. Can taste this off flavour in both my recently brewed Janets Brown Ale, Epic Pale Ale Clone and my recent session IPA. All three of these beers I calculated the mash pH to 5.4, but haven't been able to check for sure due to not owning a pH meter.

My next beer I brew I will aim for 5.5 mash pH and see if that improves the off flavour.

If anyone has any thoughts on this I would love to hear it!

If you are keeping the beer in the fermenter at 18C until bottling, you might be tasting acetaldehyde, a normal intermediate product of fermentation. It can be minimized by letting the beer warm to 22-23C after the initial ferment dies down. Leaving the beer in the bottles at room temp longer will also clean it up but it may take longer.

 

[JonM]

Well, the short answer is you really should get a pH meter. The calculators are great, but they won't tell you what the actual pH of your mash is. You could be off by a little or a lot.

 

[mikeburns]

Ok thanks for the replies guys, will try to drop the pH slightly next brew, and a pH meter will be on my radar in the not to distant future. I wounder if it is acetaldehyde... Next brew I will allow it to warm up a bit, after say 4 days of fermentation...

 

[tomaso]

I have a similar problem with a kind of slightly sour tasste obscuring my malty brews and at the moment I'm thinking it's because of me not liking Safale 04 as quite a few other people don't either...

see if it correlates with your 'sour' beers and do a search for it. I'm not completely sure yet but am close to abandoning S-04...