sour beer

my first extract brew is muntons nut brown ale. I used one can of hopped nut brown ale extract with one can of muntons light malt extract.

fermented it with nothingam yeast at steady 63 F for 10 days.

after I racked to secondary, I had to leave the carboy at room temperature which in some moments got up to 84 F (it was really hot here lately)...

beer is bottled for 10 days now and I decided to try one, just to see what's going on with it....

it has good carbonation, I think the yeast consumed all the sugar that was there...

the problem is in sourness. it tastes a bit sour, and vinegary. I didn't have any signs of infection.

I'm afraid high secondary temperatures could have made it sour. am I right?

do you reckon it will fade out with time?

what to do now? drink it all by myself and not offer it to friends, or wait for the sourness to disappear.... (if at all)....

There are two different things that often make beer taste sour. Acetaldehyde, or lactic acid usually introduced by bacteria. But you also say you only fermented for 10 days, left in secondary for ??? days, and bottled just 10 days. So it's still pretty young and the sour flavor may actually just be green beer.

Sour - Acetaldehyde

Symptoms: Tastes of grass or green apples. Strong vinegar or cider-like tastes

Causes: Premature removal from yeast; premature flocculation; to little oxygen for the yeast; bacterial spoilage; oxidation

Fixes: Full fermentation from a good yeast strain, and aeration of the wort will help prevent this.


Sour - Lactic Acid

Symptoms: Sour for sour's sake. It's a clean sour, not smelling like grass or apples. So if it tastes tart, but doesn't smell like grass or apples, it's probably lactic acid. There also might be a slight vinegar smell. Think white vinegar instead of cider vinegar.

Causes: Poor Sanitation; Acid Creating Bacteria; Some yeast strains; Excessive acid rest; Excessive mashing; storage of beer at warm temperature; Scratched fermenters (harder to clean, so more susceptible for Acid creating bacteria)

Fixes: Good Sanitation practices and using a different yeast strain is a good start. Shorter acid rests and mashing for less than two hours will also help.

marubozo said:

There are two different things that often make beer taste sour. Acetaldehyde, or lactic acid usually introduced by bacteria. But you also say you only fermented for 10 days, left in secondary for ??? days, and bottled just 10 days. So it's still pretty young and the sour flavor may actually just be green beer.

Sour - Acetaldehyde

Symptoms: Tastes of grass or green apples. Strong vinegar or cider-like tastes

Causes: Premature removal from yeast; premature flocculation; to little oxygen for the yeast; bacterial spoilage; oxidation

Fixes: Full fermentation from a good yeast strain, and aeration of the wort will help prevent this.


Sour - Lactic Acid

Symptoms: Sour for sour's sake. It's a clean sour, not smelling like grass or apples. So if it tastes tart, but doesn't smell like grass or apples, it's probably lactic acid. There also might be a slight vinegar smell. Think white vinegar instead of cider vinegar.

Causes: Poor Sanitation; Acid Creating Bacteria; Some yeast strains; Excessive acid rest; Excessive mashing; storage of beer at warm temperature; Scratched fermenters (harder to clean, so more susceptible for Acid creating bacteria)

Fixes: Good Sanitation practices and using a different yeast strain is a good start. Shorter acid rests and mashing for less than two hours will also help.

Click to expand...

I guess this is my problem. the beer was in secondary for a month - sorry for not mentioning it in the post....

it was really hot here while it was in secondary...

I get a little bit of a vinegar in overall flavor. but it is enough to be a reason not to offer this beer to anyone...

I hope it will fade out with time.

thanks for the answer anyway!