1. The wait is over! Download the BeerAdvocate app on iTunes or Google Play now.
  2. Get 12 issues / year of BeerAdvocate magazine for only $9.99!

WTF? Yeast quantity

Discussion in 'Homebrewing' started by mikehartigan, Mar 26, 2012.

  1. I brewed a German Pilsner today using WLP830. Unfortunately, I didn't have any DME so I wasn't able to make a starter. No problem - the label on WLP830 says that it's good for a 5 gallon batch (I know, I know!). Beersmith says that if I'm not making a starter, then I need 7 vials of yeast!!! What the hell does that mean? White Labs says 1 vial, Beersmith says 7. FWIW, MrMalty says 6.9 vials. These numbers just don't make sense! Why would the manufacturer say 1 when 7 are needed? Surely, the manufacturer has an interest in producing the best beer possible with his product. How does this reconcile with both MrMalty and Beersmith? (I'm not suggesting that any of these is wrong. Only trying to understand)
  2. VikeMan

    VikeMan Advocate (740) Pennsylvania Jul 12, 2009

    IMO, White Labs labels underestimates the amount of yeast typically needed. Or put another way, the number of cells White Labs thinks you need is a lot less than what Jamil (and many of us) think. With a lager, you're getting a double whammy, because a lager of a given gravity typically needs twice as many cells as an ale of the same gravity.

    Edit: that must have been some pretty old yeast though for Mr. Malty to say 7 vials. Or was your OG a lot higher than a typical Pils?
  3. spointon

    spointon Advocate (550) Illinois Nov 25, 2007

    You can make beer with 1 vial and no starter, or you can make good to great beer with 7 vials and no starter. Or you could just wait, get the supplies necessary, and make an appropriate starter...
  4. inchrisin

    inchrisin Savant (435) Indiana Sep 25, 2008

    Wait, you've done lagers in the past, yea? Is the cell count 100 billion for the vial, like the ale yeasts? If it's only 100 billion, you'll need more for a lager. I believe that the average starter size is going to be 3-4 Liters with a stir plate.
  5. spointon

    spointon Advocate (550) Illinois Nov 25, 2007

    I just looked on the White Labs online FAQ and it says this: "One thing that contributes to flavor contribution in beer is yeast growth. If less yeast is pitched into beer, more yeast growth takes place, so more flavor compounds such as esters are produced. Depending on the amount produced, this is how pitching rates can have a direct effect on flavor profile...But does a pint starter worth of yeast (30-50 billion cells) pitched into beer taste different then 2 liters worth of yeast (250 billion cells)? Sounds like more homebrew has to be made to get to the bottom of this! Your feedback is appreciated."

    Speaking from experience, you don't want to just pitch one vial or smack pack of yeast into a lager. IMO you need to heed the pitching rates you read about on Mr. Malty's site. I do, and it works well.
  6. Regarding flavor compounds and esters, why does it matter whether the yeast growth occurs in a growler or in a carboy? (I'm not arguing that it doesn't matter - I'm simply trying to understand what's going on). And if White Labs wants to be optimistic about their product, why by a factor of 7?!?!?
  7. cracker

    cracker Savant (395) Pennsylvania May 2, 2004

    To be very simplistic, yeast reproduce first before fermenting that's why it matters. That lag period (reproduction) makes all the difference in the final result.
  8. VikeMan

    VikeMan Advocate (740) Pennsylvania Jul 12, 2009

    It's not a factor of 7 for fresh yeast. (Not if your OG was around 1.050 or so.) One of the other things White Labs does is claim (or at least imply) that 4 month old yeast is as good as fresh yeast. Mr. Malty does not make that assumption.
  9. VikeMan

    VikeMan Advocate (740) Pennsylvania Jul 12, 2009

    When it occurs in a growler, you can decant the esters away. Also, if it occurs in the carboy, it will be more difficult to provide sufficient O2 for all that growth.
  10. Also remember that double the volume does not mean double the growth... If you triple your cell count before they go into the carboy, they will then grow again, giving you substantially more yeast than if you haven't grown the numbers in a starter.
  11. Just out of curiosity, I wonder how many people actually decant for a medium/low gravity beer. I know I don't.
  12. VikeMan

    VikeMan Advocate (740) Pennsylvania Jul 12, 2009

    I do almost always.
  13. If I have time to refrigerate the starter to decant, then yea, I do, but it's not a huge deal if I don't.
    EdH likes this.
  14. Update - after about 36 hours of lag time during which the temperature unexpectedly fell into the 30's, the airlock was pretty active, and there's lots of churning going on in the wort. I considered throwing in a packet of US-05 in an attempt to minimize what is likely a serious under pitch, but decided I'd just let it go and see what happens. Any damage is likely already done and irreversible at this point. The upside is that it will still be beer! :) I suspect the worst case is that my first attempt at a lager will simply not win any ribbons.

Share This Page