Long mash

Discussion in 'Homebrewing' started by jlordi12, Apr 3, 2013.

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  1. jlordi12

    jlordi12 Zealot (500) Jun 8, 2011 Massachusetts
    Beer Trader

    Anyone ever mash in the morning, go to work and come back to boil in the evening? How were your results? I did that this morning , don't know what to expect.
  2. OddNotion

    OddNotion Devotee (478) Nov 1, 2009 New Jersey
    Beer Trader

    From what I have read, a long mash can lead to a very fermentable wort, so you may have very high attenuation. How many hours are we talking and how does your tun hold temps?
  3. JackHorzempa

    JackHorzempa Poo-Bah (2,737) Dec 15, 2005 Pennsylvania

    The notion is that increased mashing time results in a wort of higher fermentability (i.e., increased attenuation). At the 2012 NHC, Greg Doss gave a presentation on his study of yeast attenuation. Interestingly he achieved maximum attenuation with a 75 minute mash and less attenuation for a 90 minutes mash. I wonder what a several hour (all day?) mash does?

    Greg’s results:

    · 75 minute mash = 85.71% AA
    · 90 minutes mash = 84.91% AA

  4. VikeMan

    VikeMan Meyvn (1,442) Jul 12, 2009 Pennsylvania
    Beer Trader

    I have read that presentation and am looking forward to Greg's followup work, whenever that happens. It should be noted that those are two single experimental observations. The general 'best fit' curve is that longer mash times resulted in higher attenuation. The experiment should (and I suspect will) be repeated multiple times, to normalize the data. I bet (but wouldn't put a lot of money on it) that the 75 minute and 90 minute data would then fit the same general trend (i.e. longer mash equals more fermentability).
  5. warchez

    warchez Aspirant (213) Oct 19, 2004 Massachusetts

    To Vikeman's point (sort of), 85.71% and 84.91% are the same # in my book. I don't know Greg Doss and I don't know what equipment he is using, but I doubt that those two measurements are actually accurate to 100th decimal place. And those two #s are meaningless being both so close together time-wise and somewhat "late" with respect to what most people mash at (i.e 60min).

    To that end, I have done a handful of overnight mashes. Set up and start mash at say 9PM, then come out in the morning around 6AM, sparge and start brewing. I have also done a couple brews where it was 24hrs. Mash at 6PM, come home the next day at 6PM and finish the session.

    In both of those cases the end result was beers I was pretty pleased with and comparable to the same recipe when done "traditionally". I don't recall what my calculated attenuation was, but who cares. The numbers are one thing, but great #s can still generate lack luster beer. My limited extended mash beers a have been great, so I don't think there is a big downside to it aside from time and stretching it out.
    Duff27 and inchrisin like this.
  6. mugs1789

    mugs1789 Initiate (183) Dec 6, 2005 Maryland

    I typically mash overnight for 6 or so hours and believe that it makes no difference compared to a 60 minute mash.
  7. hopfenunmaltz

    hopfenunmaltz Meyvn (1,243) Jun 8, 2005 Michigan

    Greg Doss is a microbiologist that works at Wyeast.
  8. mikehartigan

    mikehartigan Aspirant (290) Apr 9, 2007 Illinois

    I did an overnight mash some time ago, about 9 hours. My 10 gal Rubbermaid cooler mash tun only lost about 6 degrees during that time - from 154 to 148. This was for a Cream Ale, so I wanted it dry. OG, as I recall, was 1.062, FG was 1.002 (!!!). I reviewed the procedure and results with my brew club. The consensus was that the enzymes continued to break down sugars as the temperature dropped. The result was the same as if I had done a more conventional 60 minute mash at 148F. Seems plausible, but this was speculation, so something else may have been going on that we didn't consider. I've since used that technique for bigger beers - a DIPA, for example. I was able to dry it out without adding any sugar (I don't know if that's good, bad, or indifferent). The beer turned out just about how I expected in terms of body. I've been playing with the technique to get a better handle on just how it behaves and how I can put it to good use. I really haven't done any controlled experiments, so it's hard to characterize it beyond my observations, above.
  9. hopfenunmaltz

    hopfenunmaltz Meyvn (1,243) Jun 8, 2005 Michigan

    Many of the light beers are made with long mashes at 140F. The Beta will stay active longer at those temperatures.

    My thinking on the Greg Doss experiment was that he was mashing higher, 153F or so. The Beta will be denaturing at those temps, not instantly, but those will start to degrade.
  10. minderbender

    minderbender Initiate (189) Jan 18, 2009 New York

    Here is a post from Mad Fermentationist about a 7-hour mash that he once did. Here is how the beer turned out. Here is his advice:

  11. inchrisin

    inchrisin Defender (654) Sep 25, 2008 Indiana

    How does an .002 cream ale taste?
  12. swhite11

    swhite11 Initiate (0) Sep 15, 2008 Washington

    I feel like I read somewhere that mashing for too long can lead to higher tannin levels in the wort.
  13. jlordi12

    jlordi12 Zealot (500) Jun 8, 2011 Massachusetts
    Beer Trader

    I got 75 + percent efficiency which is my highest yet and I overshot my OG by a good margin. That coupled with the extremely fermentable wort has me a little bit worried. I did mash a little higher because I thought my efficiency could potentially be better, hopefully that will be my saving grace. Thanks for everyone who took the time to chime in. Cheers
  14. antlerwrestler19

    antlerwrestler19 Disciple (363) Nov 24, 2010 Nebraska
    Beer Trader

    My main worry would be extracting extra tannins from the husk of the grain. I have never tested this theory so I can't necessarily support it but I've read it in numerous brewing texts and tried to avoid it since.
  15. sergeantstogie

    sergeantstogie Aspirant (202) Nov 16, 2010 Washington

    I can't look up blogs while in the office, but I think The Ale Apothecary does a really long mash.
  16. mikehartigan

    mikehartigan Aspirant (290) Apr 9, 2007 Illinois

    A little drier than I would have preferred. If it wasn't for the 30% flaked maize, it would have had virtually no flavor. That said, it was a great lawnmower beer, which is what I was going for.
  17. jlordi12

    jlordi12 Zealot (500) Jun 8, 2011 Massachusetts
    Beer Trader

    Can you get a DUI or an open container citation on a John Deere?
    mikehartigan likes this.
  18. DubbelMan

    DubbelMan Initiate (0) Mar 17, 2009 New York

    Yes. ;)
  19. mikehartigan

    mikehartigan Aspirant (290) Apr 9, 2007 Illinois

    I didn't note any harshness that I would associate with tannins. It was also a very clean fermentation. It lacked flavor in the same way that a very dry wine lacks flavor (some will argue with that, but that's how I perceive it).
  20. sergeantstogie

    sergeantstogie Aspirant (202) Nov 16, 2010 Washington

    Do yourself a favor and google arrest+lawnmower+taser+drunk

    One of the funniest videos I've ever seen.
    jlordi12 likes this.
  21. AlCaponeJunior

    AlCaponeJunior Initiate (0) May 21, 2010 Texas

    I now have 3:02 fewer minutes to live thanks to having watched this video. :rolleyes:
    sergeantstogie likes this.
  22. jlpred55

    jlpred55 Initiate (0) Jul 26, 2006 Iowa

    I do long mashes all the time. Sometimes over the day but most the time overnight 7-9hrs. I've had zero issues with the whole process and I never seem to over-attenuate. I usually start the mash much higher, 5-7 deg higher than I normally would. My mash tun is well insulated, lid, etc and I wrap it in a high quality sleeping bag. I've gone long, like 12 hours before with no issues.

    here are certian styles I won't do long mashes on but most of the styles I brew, IPA, PA, Ambers, blondes, helles, pils, etc....I will do it. It is good to add a nice hot sparge to it to help losen it up to prevent slow run off, which happens a lot with the temps dropping.
  23. jlordi12

    jlordi12 Zealot (500) Jun 8, 2011 Massachusetts
    Beer Trader

  24. sergeantstogie

    sergeantstogie Aspirant (202) Nov 16, 2010 Washington

    Quote from Paul Arney's Ale Apothecary facebook page. He used to be a brewer at Deschutes and has been the man behind several pretty damn good beers.
    "I'm not really looking to maintain as much as develop...I insulate the barrel and lose 10-15 degrees over the 12-15 hours. I hit both alpha & beta, but also get protease activity due to the temp drop & duration. Plus there are all sorts of critters livin' in that wood that get to add their 2 cents. Like many processes in my brewery (carbonation, for instance), the step is functional as well as uniquely flavorful. That's the definition of 'house flavor' to me!"
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