Could it be a temperature problem?

Discussion in 'Homebrewing' started by redgorillabreath, Dec 31, 2015.

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  1. redgorillabreath

    redgorillabreath Zealot (511) Mar 29, 2015 Pennsylvania

    Hello all. I'm checking again to request some of the expert advice that's out there in BA Land.

    I think that I have stalled fermentations because of the low temperature in my basement, particularly in the winter. It's currently 62F, and bottomed out last winter at 58F. All of the batches mentioned below were quite tasty, but I want to be able to get the ABV up to where it needs to get certain styles "right". Here's some data:

    Tripel/5-gal OG=1.085, FG after an extended rescue mission in Summer = 1.015
    SMASH Ale/5-gal OG=1.052, SG into secondary = 1.030
    Saison/5-gal OG=1.054, SG into secondary = 1.027
    Pumpkin Stout/5-gal OG=1.080, SG into secondary = 1.036
    Smash Ale/10-gal OG=1.052, SG into secondary = 1.027
    Tripel/10-gal OG=1.086 still in primary&bubbling every 10 seconds after 7 weeks
    Peated Stout/5-gal OG=1.063, current SG=1.038 after 3.5 weeks in primary

    When I move a batch into secondary, it's generally because activity has ceased and the yeast has dropped.

    In the case of the Tripel/10-gal batch (next to last), the bubbling had stopped while it was in the basement, but the yeast was still almost completely suspended. After I brought it upstairs where temp is 68F, activity picked up.

    For the last 4 batches mentioned above, I made big starters in hopes of driving the SG home. However, while I have more than vigorous fermentation at first, things still peter out after a week or two and I get about the same SG as with batches fermented with a single Smack-Pak, etc.

    From trolling through threads on BA over time, it looks like the elite brewers avoid these problems by moderating the temperature during initial fermentation, and then warming the brew to ~68-70F to achieve full attenuation.

    I don't have problems with off flavors, spoilage, etc.

    So is it likely that proper control of fermentation temperature is the problem?

    If so, is there a preferred method? One of my personality defects drives me to perhaps over-engineer things, so I'd be inclined to go for fairly precise control. Also, I'd like the capability to have more than one going at a time, so the $$$ involved in putting together multiple heaters+controllers could be a drag. Maybe something along the lines of a chest freezer in heating mode is the ticket?

    Many thanks in advance (again)!

    Cheers!!!
     
    #1 redgorillabreath, Dec 31, 2015
  2. Brew_Betty

    Brew_Betty Initiate (0) Jan 5, 2015 Wisconsin

    Are these all grain batches? If so, it sounds like you have a mash conversion problem.

    Your 62F basement should be fine for most ale yeasts. It would be helpful to know which yeasts you used.
     
    #2 Brew_Betty, Dec 31, 2015
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  3. GormBrewhouse

    GormBrewhouse Pooh-Bah (2,111) Jun 24, 2015 Vermont
    Pooh-Bah

    Couple questions,

    What was your mash temps

    Do you measure the air temp or the temp of the beer?

    You could get a heating mat, like what some use for starting flowers, with a thermostat, then surround fermenter with . Styrofoam board insulation. I do this and can ferment beer very close to what I want. It is no good if you require cooler temps.
     
    #3 GormBrewhouse, Dec 31, 2015
  4. DunkelFester

    DunkelFester Zealot (607) Aug 24, 2004 Pennsylvania

    There's a pretty easy way to find out: ferment in a warmer room elsewhere in your house once and see what happens.

    Some yeast will be perfectly happy at 60F. Others may stop working altogether (or go so slowly that you wouldn't know the difference). ALL, otoh, will work more quickly at 68 - 70.

    So, if you ferment somewhere warmer and you're still only 50% AA after 3 weeks in primary? You've got other problems (like unintentionally high mash temps resulting from a broken thermometer? Just one possibility).

    Either way - you can't move your beer out of primary while the gravity is still that high. In order to have any shot at getting better attenuation, you need to leave it on the yeast cake until you're within a few points (at most) of your target.
     
    #4 DunkelFester, Dec 31, 2015
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  5. PapaGoose03

    PapaGoose03 Grand High Pooh-Bah (6,057) May 30, 2005 Michigan
    BA4LYFE Society Pooh-Bah

    Is your fermentor sitting directly on a concrete basement floor? The temp at that level could be 3-4 degrees colder than the ambient room temp, thus making it less than ideal for the yeast that you're using.
     
    #5 PapaGoose03, Dec 31, 2015
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  6. redgorillabreath

    redgorillabreath Zealot (511) Mar 29, 2015 Pennsylvania

    In order of appearance:
    Mix of WLP568 + Wyeast 1762
    US-05
    WLP658
    Wyeast 3724
    US-05
    Mix (see above) harvested from secondary.
    Wyeast 1728

    Mash temps: I've generally been doing a stepped mash in the kettle, then transferring into the tun for lautering and batch sparging. Mash is 20 min @ 120F, 60 min @ 153F, up to 170F then transfer.

    The carboys sit on 2x4's instead of directly on the floor. The 62F is the air temp at carboy height (top). Mothergoose is exactly right about the temperature variation on the floor vs 2 or 3 feet up.
     
    #6 redgorillabreath, Jan 1, 2016
  7. redgorillabreath

    redgorillabreath Zealot (511) Mar 29, 2015 Pennsylvania

    By the way, I had to force carbonate the pumpkin stout. After 3 weeks in bottles it was flat. So I dumped and kegged.
     
    #7 redgorillabreath, Jan 1, 2016
  8. utahbeerdude

    utahbeerdude Maven (1,374) May 2, 2006 Utah

    Based on your data (good mash procedure and making starters for some of the underperforming fermentations), it seems as if you may be putting your yeast to sleep a bit early. Are you doing a good job of aerating or oxygenating? This definitely can have an effect.

    I personally am a fan of raising the temperature as the fermentation just begins to slow down. For example, if initially fermenting the beer at 65 F, I'll raise the temperature into the low 70s over the course of a few days. My rate of raising the temperature depends upon the effect of the temperature ramp on the fermentation activity: I try to maintain a relatively constant fermentation rate during the ramp. I'll leave it at the higher temperature for typically a week before packaging or lowering the beer to lagering temperatures.
     
    #8 utahbeerdude, Jan 1, 2016
  9. Brew_Betty

    Brew_Betty Initiate (0) Jan 5, 2015 Wisconsin

    s05 and wy1728 both have no problem fermenting in the high 50s. 62F ambient isn't too low for either or them. My last batch with 1728 was fermented at 60F with no temperature control and no heat belt to raise the temp near the end. It finished in less than a week.

    So I still suspect you have a mash conversion problem. This could be due to step mashing in the kettle without a false bottom. When you heat from 120F to 152F, the grain sitting on the bottom of the kettle is probably going to get hot enough to mash out before it can completely convert.

    My advice is to try a single mash step at 152F. No mash out. Drain, sparge, drain. Be sure the mash pH is in the 5.2-5.6 range.
     
    #9 Brew_Betty, Jan 1, 2016
  10. JackHorzempa

    JackHorzempa Grand Pooh-Bah (3,375) Dec 15, 2005 Pennsylvania
    Society Pooh-Bah

    Do you know the temperature of the liquid in the fermenter? For example do you have a fermomter on your primary?

    http://www.northernbrewer.com/fermometer

    Cheers!
     
    #10 JackHorzempa, Jan 1, 2016
  11. redgorillabreath

    redgorillabreath Zealot (511) Mar 29, 2015 Pennsylvania

    Dear Brew Betty - I'm going to try this, or maybe even step to the dark side and do an extract batch instead of grain to see how it goes. For what it's worth, in the Tripel/10-gal batch, the whole thing was too big to fit in my tun. I mashed half in the kettle (stepped w/ 170 mash-out) and half in the tun(120F and 151F, then drain). The SGs of the two worts (pre-boil) were 1.063 vs 1.061, but I suppose that's telling me how much stuff was extracted, not how much conversion there was?

    The other thing that I'm probably weak on is aeration. I just let the wort free-fall into the fermenter when I rack it out of the kettle (following cooling). I guess I need to step up to something more aggressive.

    I have one, but I just can't commit to applying to a carboy. I have a surface contact thermocouple that I use from time to time. After things are settled down, carboy surface temp = room temp. I haven't studied the temp during the first couple of days, where there may be a difference.

    Thanks/Cheers!
     
    #11 redgorillabreath, Jan 2, 2016
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  12. Brew_Betty

    Brew_Betty Initiate (0) Jan 5, 2015 Wisconsin

    You can get the right OG and have a less fermentable wort than desired. I think that is the problem. For example, mashing at 152F will give you the fermentability you want, but in your case at least some of the mash was exposed to a higher temperature which reduces fermentability.
     
    #12 Brew_Betty, Jan 2, 2016
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