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Brewing over multiple days

Discussion in 'Homebrewing' started by SaintBenedict, Apr 3, 2012.

  1. As I learn more about home brewing, I wonder how crucial it is to see the entire pre-fermentation brewing process through in one day. Not that I have any plans to do this, but I am curious if anyone has done the mash and the boil on separate days—by necessity or by design. Considering that the wort will ultimately be boiled, I figured that contamination would not be an issue.

    Disclaimer: I'm new to home brewing, so please keep that in mind as you consider my rather naive question. :)
  2. If you let a mash sit out for an extended period of time there is a good chance you will begin to have a lot of lacto growth and will produce a tart or sour beer depending on the length of time you let the lacto grow. This method can be used in berliner weisse beers and is called a sour mash. While boiling will kill the lacto, the damage is done and the beer will more than likely have that tart twang to it.
  3. I just brewed a berliner weisse for the first time. It was nice to get to spread out some of the work, and it's one of my favorite styles. I mashed and sparged normally an let the wort sit for a couple days to sour up. Just added some raw grain in a mesh bag and let the lacto do its thing. 3 days later I took the bag out and started the process as usual from the boil. Also a nice 15min boil to boot. Probably the least stressful, for lack of a better word, brew I've made yet. Hopefully it comes out good.
  4. jbakajust1

    jbakajust1 Moderator (685) Oregon Aug 25, 2009 Staff Member Verified

    To echo what others have said, sour mashing can can be spread out over the course of a few days, but the brewday can be chopped up as well with out souring. There were tons of threads on the old forum about over-night mashing, ie, mash your grains on Friday night, bundle it up, and leave it over night until morning when you run off, sparge, boil, chill, pitch, ferment on Saturday morning, or even mash before work in the morning, then runoff, sparge, boil, chill, pitch, ferment after you get off. Just don't leave the clean up for a few days, rancid grains are vile, and stuck on wort is difficult to remove, and can mold (or grow souring bacteria that can transfer and infect your wort depending on what you wait to clean).
  5. VikeMan

    VikeMan Champion (930) Pennsylvania Jul 12, 2009 Verified

    To OP: to be perfectly clear, what they are describing is a 'sour mash' which is something you normally don't want to do unless you are brewing a specific style (like a berliner weiss) that calls for it.

    You could, however (I suppose), freeze your wort and brew later without picking up sour lacto (a bacteria).
  6. Thanks for the input everyone, and for he clarification VikeMan. Since the brewing process seems to be naturally divided in separate stages, it got me thinking if splitting the steps was ever done, either out of necessity (an unexpected event that would prevent one from continuing, for example) or according to a plan (as with the previously mentioned sour mash technique).

    As for storing the wort to be brewed later, how do you suppose it would last in a sealed container in the fridge for a day? Again, I don't anticipate doing this, but between work, kids and other distractions, sometimes you never what your day will bring. Besides, it would be nice to know that a batch isn't ruined just because of some unforeseen circumstance.

    Finally, in regard to sour mashing, is this exclusive to the Berliner Weiss style, or do other styles make use of this approach? The flavored Berliner Weiss beers that I've had have been considerably sweet, so I never picked up on the 'souring'.
  7. Does the growth of lacto adversely affect the amount of fermentable sugars in the wort, and thus the potential alcohol level of the beer?
  8. From what I have read, Lacto will ferment some sugars but does not produce alcohol so I would assume that it could theoretically take away some of the fermentable sugars which could lower the abv. This I am not positive on but it is just my line of thinking, someone please correct me if this is inaccurate.
  9. Berliner weisse beers are traditionally sweetened post fermentation and prior to serving which is an attempt to take away some of the tart flavor which some find less desirable.
  10. VikeMan

    VikeMan Champion (930) Pennsylvania Jul 12, 2009 Verified

    I'd do it rather than throwing away a batch of wort, but I would try pretty hard to not have to do it.
  11. jbakajust1

    jbakajust1 Moderator (685) Oregon Aug 25, 2009 Staff Member Verified

    If you were to bring it up to a boil for maybe 15 minutes before putting it in the fridge (Sealed of course) that might keep it from souring in 24 hours. Your best bet would be to boil briefly, chill, seal, fridge.

    Any sour type beer would work with a sour mash. You can sour it slightly to add some twang to a Saison or Irish Dry Stout, you can sour it fully to start on an American Wild, Flanders Red, Oud Bruin, Lambic, Gose, Berliner Wiesse. Just make sure you do it right... mashing, then leaving it sit for 4 days won't just sour the mash, it will putrify it, lots more stuff than lacto can grow depending on temp and exposure to oxygen.
  12. quirkzoo

    quirkzoo Initiate (0) Colorado Jul 7, 2011

    One time I split up a brew over two days.

    My first all-grain batch I did a brew in a bag technique but it was so cold outside (brewing in my garage) it took forever to get the water up to temp. Because of this it was too late for me to finish brewing that night. So I covered the pot and let it sit overnight and finished the next day. The wort went from ~150F to about ~40F and it took me even longer to get it up to boiling the next day, I kind of wish I had just finished the beer the previous night.

    As for leaving the wort out overnight before boiling, there was absolutely no lactic twang perceivable, but as I said, it was really cold out so that probably cooled the wort quickly enough that it didn't stay in the ~100F range for very long, which is where lacto thrives.

    So basically you can split it up, but because of other factors, you will probably wind up spending even more time.
  13. leedorham

    leedorham Champion (845) Washington Apr 27, 2006

    As for the concerns about lacto from an overnight mash - If you use a clean, fairly airtight cooler (which you should have anyway) and mash high it shouldn't be that much of a concern. Just dough in at 160, shut the lid, and don't open it again until you're ready to sparge.

    If you did that, I would be very surprised to see a worrisome amount of any microbe. As far as effect on the finished product, I can't really say without trying it myself first.
  14. What might one expect from this long of a "sac. rest"?

    -Will efficiency be greatly affected by letting the grains mash for 10 hrs?
    -If the desited mash temp was 150, I'm asuming the mash would drop significantly overnight. Are there any adjustments to recipe design that should be made to account for long "rests" at lower temps?
    -Is tannin extraction an issue?
  15. leedorham

    leedorham Champion (845) Washington Apr 27, 2006

    I can't answer any of those with anything but speculation. If you started at 150, I imagine you'd end up with a highly fermentable, thin bodied wort. In the BYO article where the guy makes the all-grain 20 percenter, he mashes overnight. I can't recall what the temp drop was but his goal was to get as fermentable a wort as possible.
  16. mnstorm99

    mnstorm99 Advocate (535) Minnesota May 11, 2007

    I am about to try splitting it up by mashing and collect on a Friday evening, cover the pot and put all the cleaned mash equipment away. Then when I get up Saturday morning I'll start up with the boil. This is a good process for back-to-back days.
  17. I did an overnight mash a year or so ago for a Cream Ale. Temp dropped from 154 to 148 over 9 hours -- not too bad, IMO. And evidently not long enouh to develop any lacto. It fermented down to 1.002! It's fortunate that I wanted this beer super dry. A very effective technique, but I would advise extreme caution.
  18. dgs

    dgs Aficionado (195) Pennsylvania Jul 18, 2005

    Another way many brewers split up their brew time is with "no chill" brewing. Basically, they mash and boil, but delay pitching the yeast until after the wort has cooled at a much slower rate than would have happened with a wort chiller or icebath. I think this became popular because of water conservation, but it also provides the opportunity to time shift the brewing steps.
  19. dfess1

    dfess1 Initiate (0) Pennsylvania May 20, 2003

    I mashed, collected, and put it directly into a clean/sanitized carboy about 2 months ago. Went and played hockey. Then threw it back in the BK 3 days later and brewed it. Alot of people that have a hell of alot better pallet than I have been pretty impressed with the beer, and there's no souring going on in it.
  20. Did you ref
    Did you refrigerate it, or let it sit at room temperature?
  21. crosamich

    crosamich Savant (270) Florida Nov 28, 2007

  22. kjyost

    kjyost Champion (775) Manitoba (Canada) May 4, 2008 Verified

    One of the guys in our club mashes overnight and does a partial boil all-grain (his kettle can only do 17L and he ferments 23L). He says for his system he mashes at about 2-3F higher than what he says a recipe normally suggests and he hits his FGs well (and he has a few awards to show for it, so it isn't just him)
  23. dfess1

    dfess1 Initiate (0) Pennsylvania May 20, 2003

    sat at room temperature in my insulated but unheated garage.
  24. Utawana

    Utawana Aficionado (130) New York Nov 7, 2007

    I break up the brew day into two more often than not. I mash and sparge the night before, then boil the next day.

    Since I collect the runnings before going to bed, there is no sour mash to worry about. If you heat the wort up to stop conversion (you can start that right after you collect the first runnings), no worries there either.

    This works well for me - after the kids go to bed, I start the process. The next day I restart at a strategic time and I do not have to devote an entire afternoon effectively isolated from the family.... although that has an appeal... it is unrealistic for me.
  25. What does "stop conversion" mean? Sorry, I looked online so I wouldn't have to bother you requesting clarification, but I can't seem to find it googling "brewing terminology".

    Haha. I have been brewing after hours as well. Nice to know it's not a big deal if I want to knock off early and pick up the next day where I left off. Am I correct in assuming that you also cover the wort and allow it to sit at room temperature?
  26. kjyost

    kjyost Champion (775) Manitoba (Canada) May 4, 2008 Verified

    When you run off your runnings, there are still active enzymes in there (unless you mashed out, and even then some may make it through, I am not sure). So you need to denature (break up and stop) the enzymes from being active and being able to chop down the long chains (dextrins) into more fermentable sugars (glucose, etc...). While you need this in a mash to make fermentables, you don't want it to be too fermentable as you will end up with a thin bodied beer (the same effect as mashing really low).

    I may have a few of the pure scientific terms off here, but the basic idea is correct :)
  27. So, the stop conversion ins essentially accomplished by mashing out at 170° before the sparge?
  28. VikeMan

    VikeMan Champion (930) Pennsylvania Jul 12, 2009 Verified

    That is indeed the purpose of a mashout.
  29. Utawana

    Utawana Aficionado (130) New York Nov 7, 2007

    Looks like someone else covered the conversion thing (heat the liquid you have collected from the mash to ~180) - to reiterate this will "stabilize" the wort, keeping the fermentable and unfermentable sugars in a similar ratio overnight. Heating the wort to this temp also effectively pasteurizes it, but the mash temps pretty much take care of that.
    Yes, I will let the kettle sit there overnight in ambient temps. More often than not I will partially cover it, but sometimes I don't. I like to let steam escape the kettle - probably more voodoo than science, especially at preboil - I feel that there are some volatiles that I don't want recycled back into the wort from condensing on a lid. If the fruit flies are out, I'll partially cover.
  30. Thanks for the breakdown, Utawana.
  31. mugs1789

    mugs1789 Savant (275) Maryland Dec 6, 2005

    I have gotten into the habit of overnight mashes for most of my brews. I mash-in around 10 or 11pm after the kids are in bed and collect my first runnings around 6 or 7 the next morning. I typically lose 5-7 degrees temperature overnight, from 152 to 145ish. I haven't noticed any off flavors, sourness, or signficantly increased efficiency. This method works well for me.

    My only reservation is when using darker grains. I brewed a stout with this method a few years ago and it was excessively astringent. I'm not sure if it was the overnight mash with the black patent malt or just my recipe in general. The next time I use highly roasted malts, I'll brew it all in one session.
  32. Do you find that the drop in temp and lack of mash out makes the wort more fermentable? I would be worried that hours spent in the high 140s with enzimatic activity would make the beer too thin.

    Whacha think?
  33. mugs1789

    mugs1789 Savant (275) Maryland Dec 6, 2005

    I haven't noticed this.
  34. I have definitely found this to be the case. I've had beers go from 1.070+ down to 1.002. Fortunately, these were beers I wanted to finish dry, so it was ok. I use the overnight technique frequently, but very selectively.
  35. Good to know.

  36. mnstorm99

    mnstorm99 Advocate (535) Minnesota May 11, 2007

    Something I was thinking about for you overnight mashers. Does an overnight mash really save any time on the second day? If I take an hour mash and 30 minutes to mash in, as opposed to 45 minutes to get my sparge water up to temp on day two...I am really only saving 45 minutes on day two.

    I still like the mash, sparge, collect and clean the mash equipment (two hours day 1), then boil, cool, pitch and clean boil equipment (two hours day 2). This seems like a much better system to split the process up.
  37. Not sure I understand your question. If I spend 2 hours on day one, that's roughly 2 hours I save on day 2. But I don't really do it to save time. I do it to get a more fermentable wort. The time 'saved' on day 2 is just a bonus. Now, if day 1 is more free than day 2, this can be the difference between brewing and not on day 2.
  38. mnstorm99

    mnstorm99 Advocate (535) Minnesota May 11, 2007

    Just seems to me, starting with heating up the sparge water there is still about 3 hours left. My typical brewday is four hours.

    Doing it for the reason of fermentation is a different reason to do it...and I may try it for that reason.
  39. mugs1789

    mugs1789 Savant (275) Maryland Dec 6, 2005

    It saves me about an hour, maybe less. More importantly, it shifts some brewing time from a weekend morning (typically busy family time) to Friday or Saturday night, after the kids are in bed.
  40. kjyost

    kjyost Champion (775) Manitoba (Canada) May 4, 2008 Verified

    Yup, that's why I have started to measure my strike & sparge water out the night before, along with grinding the grains...

    I am sure glad I did that last night otherwise my kids would have learned some new verbiage due to the incredible PITA that grinding my wheat berries turned out to be (flipped the Barley Crusher all over the floor a couple of times, my cordless drill didn't have the torque to grind them, etc...)