Pilsner Appley Taste

[warpy55]

I made a Pilsner beer and kegged and bottle the result. I lagered it for 6 weeks in bottles and keg. I tasted the keg and it tasted fruity and appley. The bottled versions do also. It was an all grain batch and I boiled it for 90 minutes to get rid of DMS. Question, is there anything I can do to get rid of the appley tatse. If I introduced new yeast would it get rid of the DMS? or blend it or is it just a dumper?

 

[BrewerBrad82]

DMS is like cream corn, not apple. What you likely have is acetaldehyde. My guess is either the lager was underpitched, or the yeast was not in great health.

https://beerandbrewing.com/off-flavor-of-the-week-acetaldehyde/

 

[slohiker]

So, I've had something similar once, it tasted distinctly like apple or cider, but not really in a good way. I'm pretty sure there's a bacteria that produces that, common with fruit flies... I think on mine, I had open fermented, and definitely had some fruit flies fall in or get into the starter... I still drank it and lived, it just wasn't very good. Just found it in my notes... Acetobacter in smaller amounts tends to cause that flavor. Hope that helps!
For what it's worth, I've continued to use all the same equipment and had plenty of good beer since, in just being more careful with starters and fermenting closed lid.

 

[TheMadKing]

DMS is like cream corn, not apple. What you likely have is acetaldehyde. My guess is either the lager was underpitched, or the yeast was not in great health.

https://beerandbrewing.com/off-flavor-of-the-week-acetaldehyde/

Spot on

I'll add that acetaldehyde can be formed from oxidation of ethanol too. So if it appeared only after lagering, this is the more likely culprit IMO.

Acetaldehyde can be potentially cleaned up by pitching actively fermenting wort into the beer (Krausening), but its not going to age out.