Ask The Brewmasters

  • 1.  Acetaldehyde with 34/70

    Posted 05-19-2023 07:28

    Hi folks,

    We have more acetaldehyde than desired in a lager made with W34/70. It is a pretty constant feature in every batch, with occasional batches rising way beyond the acceptable level as registered in sensory. 

    I know there are a lot of levers you can pull with acetaldehyde and many of them are strain dependent, so I was wondering if anyone out there has had a similar problem with 34/70 and could share what approach they successfully employed to reduce it.

    There are plenty of resources and discussions out there already on acetaldehyde formation so I'm not asking anyone diagnose my specific issue, just wondering what approaches have worked for you with this strain.

    Cheers,
    Francesco



    ------------------------------
    Francesco Mayell
    Senior Brewer
    Brixton Brewery
    London
    02036098880
    ------------------------------


  • 2.  RE: Acetaldehyde with 34/70

    Posted 05-22-2023 20:11
    We have not had any acetaldehyde problems with 34/70. Our procedure is:
    ferment between 48 F and 50 F
    diacetyl rest of 56 F at 1-2 P above terminal
    hold until no diacetyl or sulfur detected
    slow drop to 45 F
    Hold for 2 weeks
    Crash to 32 F
    add Biofine and transfer to lagering tank
    Hold for 2 weeks, while topping up carb

    The D rest is the crucial part.


    --
    Alex Kopf
    Lead Brewer
    Northwoods Brewing Company





  • 3.  RE: Acetaldehyde with 34/70

    Posted 05-23-2023 18:56



    Original Message


  • 4.  RE: Acetaldehyde with 34/70

    Posted 05-23-2023 13:45

    Hey Francesco,

     I have had success with reducing by-products of fermentation in my lagers(34/70 and S-23) using a pressurized fermentation setup. I use a spunding valve on the blow-off of the tank set to 10psi, and will hold that pressure throughout fermentation. Fermentation typically 57-59F, producing a very clean product even at the end of ferment prior to cold maturation. At least from a sensory perspective both Acetaldehyde and Diacetyl are not present in the beer by the cold maturation phase. I still do a Diacetyl rest, at 62F to be sure the yeast has cleaned up. 

    Cheers! 



    ------------------------------
    Brian Sullivan
    Brewer
    Contrast Artisan Ales
    Chamblee GA
    510-379-8650
    ------------------------------



Related Content