Krausening lite lager

Hi, brewing my fourth iteration of a light lager, seem to keep having diacetyl problems with this style. Not so with other lagers.

I've been krausening with quart of high krausen starter to reduce diacetyl.

Question on krausening, any problem just adding fresh wort, saved from the brewday (canned), directly to fermenter without yeast? Seems it would have the same effect of getting yeast back at full health to digest the diacetyl...right?

adrock430 said:

Hi, brewing my fourth iteration of a light lager, seem to keep having diacetyl problems with this style. Not so with other lagers.

I've been krausening with quart of high krausen starter to reduce diacetyl.

Question on krausening, any problem just adding fresh wort, saved from the brewday (canned), directly to fermenter without yeast? Seems it would have the same effect of getting yeast back at full health to digest the diacetyl...right?

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No, I don't believe this will have the same effect. The point of krausening is to take healthy yeast that are in the exponential growth phase of fermentation, and put them into an environment that has very little residual, fermentable sugar. These krausened yeast then move into the stationary phase where the begin reabsorbing certain compounds in the solution, like diacetyl and acetaldehyde. My thought is that if you just add a small amount of wort to already fermented beer, the standard 3-phase fermentation timeline will not occur, and thus yeast will never enter the stationary phase to absorb diacetyl.

Why do you think you're having diacetyl issues with this beer but not other lagers? Using a different yeast?

I'm thinking of adding 1 g to 4 g to krausen. My thought process is that yeast would start digesting that and I'll have yeast at the same stage in the fermenter as a high krausen externally.

I use the same yeast for all my lagers, pitch and aerate well. I'm starting to think it is the low FAN from such a high adjunct mash causing the diacetyl and will start adding yeast lysate on brew day.