Beer Forum

I have tried to make a pilsner lager couple of times, but each time I get nasty taste in it. I am assuming it is diacetyl, corn like taste. Does not go away with with lagering. I have made relatively small starters, 1 to 2 qts.. Is that what the problem is? 5 gal, All grain, Czech pils, WY2124, fermented at 48deg.

Brewzhnev wrote:I have tried to make a pilsner lager couple of times, but each time I get nasty taste in it. I am assuming it is diacetyl, corn like taste. Does not go away with with lagering. I have made relatively small starters, 1 to 2 qts.. Is that what the problem is? 5 gal, All grain, Czech pils, WY2124, fermented at 48deg.

for lagers i do a 3L starter for a 5 gallon batch. Start it up like John Palmer describes in how to brew.

Sounds like you need a diacetyl rest. Ferment the fucker at 50F for 3 weeks. Then warm it up for two days. Transfer to secondary and off to larger land....

Brewzhnev wrote: I am assuming it is diacetyl, corn like taste.

Diacetyl is an intermediate product of fermentation. It has a buttery sort of taste/aroma. To fix, perform a D-rest or add fresh fermenting yeast to clean up the brew.

DMS = Dimethyl sulfide is a component of some malted barley and has the cooked corn flavor you described. To fix, boil the wort longer.

To answer the starter question... I use the excellent pitching rate calculator on http://www.mrmalty.com. For most normal gravity lagers, it comes out to about 3 L. I usually start with about 750 ml and one yeast package or vial and then step that up to the 3 L.

Thanks for the advice. This is definitely cooked corn taste. I am not sure what malt was in that all grain kit, but I did boil it for 90 min. Single temp mash at 154 deg. This time I got Weyemanns Pils malt. I’ll am going to mash it at single tem again , but boil it for couple of hours. It does make sense, some time ago I used extract lager kit and did not have that taste in it. How long do you boil you lager worth?

I boil for 90 min and chill very quickly. DMS can still be made if the wort remains warm (above 140 maybe?) for extended periods of time. I get it below 140 within a couple minutes.

A couple more thoughts for what it's worth:

I vaguely remember someone (JZ?) saying that if you use a lid or any cover that traps steam in your kettle, then the DMS will collect on the inside along with the condensate and fall right back into the kettle.

Additionally, make sure your boil is "vigarose" enough, it's the churning and bubbling action that drives off DMS.

Brewzhnev wrote:I have tried to make a pilsner lager couple of times, but each time I get nasty taste in it. I am assuming it is diacetyl, corn like taste. Does not go away with with lagering. I have made relatively small starters, 1 to 2 qts.. Is that what the problem is? 5 gal, All grain, Czech pils, WY2124, fermented at 48deg.

In a word... yes.

Small starters stress out the yeast and they kick out a lot of diacytl. While it is true that you can do a d-rest (villiam, are you listening?), there is only so much that they can clean up. Like Madtown said - check out www.mrmalty.com for the exact amount.


Mylo

+1 on both Madtown & Sheen's advice. Spot on. It is DMS, not diacetyl.

You may need to boil a little more vigarously, too. Remember to compensate with extra water in the boil.

HTH-