Beer Forum

The local brewery (Forge Brew Works) in my area has what they call a Berliner Kolsch. It has the sourness/tartness of lacto but they said it was fermented with a lager yeast at higher temps to give it that flavor. Do you guys have any idea what kind of yeast would produce that sourness by stressing them out at a higher temperature? The beer was quite enjoyable. Thanks.

An infection.

They probably fermented with a Kolsch strain & added some bugs at the end.

They may have done a sour mash, too.

He said no bugs at all. Maybe he's lying.

That or he dumped in a bunch of lactic acid from a bottle.

Since I don't know the brewery, I will state the rude option: they inadvertently made an infected beer. It managed to taste good, and so they stretched the truth.

adamK wrote:Since I don't know the brewery, I will state the rude option: they inadvertently made an infected beer. It managed to taste good, and so they stretched the truth.

That was my first idea, but I tried to give them the benefit of the doubt.

"We didn't add bugs... our cleaning sucks & they added themselves."

Also, fermenting a lager yeast warm is the opposite of a Kolsch