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  • 1.  Average days at Diacetyl rest

    Posted 09-20-2023 11:55

    Hello,

    We are resting our lagers at D-rest (55F) for an average of 3-5 days after terminal, before our VDK sniff test is clear. I'm curious to what others are experiencing here?

    Thanks,
    Zach



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    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
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  • 2.  RE: Average days at Diacetyl rest

    Posted 09-21-2023 13:31

    Zach,

    We have been running a D-Rest of around 5-7 days that begins when the beer is past 50 percent apparent attenuation. The D-rest concludes at terminal gravity, and a go/no go on a forced VDK rest. Cheers!



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    Eamon Mahood
    Assistant Brewer
    Burgh'ers Brewery
    Pittsburgh PA
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  • 3.  RE: Average days at Diacetyl rest

    Posted 09-22-2023 13:31

    Hello Zach,

    I agree with the earlier submissions and diacetyl rest times have now been reduced to 2-3 days.

    I will advise a combination of

    (1) addition of alpha acetolactate decarboxylase enzyme into the cold wort before fermentation.

    (2) Temperature free- rise after active fermentation at 55F, once apparent extract (AE) of 3.0 +-0.5 deg Plato is achieved.  At this AE, the temperature is allowed to free rise from 55F to 60-62F. This will ensure mop- up of any residual diacetyl and generally diacetyl is substantially reduced or removed within 2-3 days.

    Further Analytical and sensory test will help determine the choice of 2- or 3-day diacetyl rest. 

    Best Regards,



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    Chika Ezeani
    Brew Master
    Kerry, Americas Region
    Beloit WI
    (608) 201-9707
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  • 4.  RE: Average days at Diacetyl rest

    Posted 09-21-2023 15:19

    Hey Zach,

    We ferment our Lagers at 50F, I usually will kill the glycol and let the tank free rise with about 2P left. It will get up to anywhere from 62-65F depending on time of year. Once I read two consecutive days of stable gravity I'll do a force test and if it passes I begin crashing. If it doesn't, I let sit another 24 hours and it's always cleaned up by then. We've never gotten diacetyl in sensory with that method. Hope that helps!

    Ronnie Chesson

    Lead Brewer - Braeloch Brewing

    Kennett Square, PA



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    Ronnie Chesson
    Lead Brewer
    Braeloch Brewing
    Kennett Square PA
    (610) 612-9242
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  • 5.  RE: Average days at Diacetyl rest

    Posted 09-22-2023 09:11

    Dear Zachary:

    Have you considered using an enzyme to eliminate the Diacetyl Rest altogether? There are some products out there that prevent the formation of Diacetyl through direct conversion of α-acetolactate to acetoin (thus no diacetyl formation).

    Let me know if you want some information.

    Cheers,



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    Dirk Loeffler
    SEKA Chemicals, LLC
    (404) 229-7583
    colognedl@live.com
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