I've been having some mash conversion/efficiency problems

Discussion in 'Homebrewing' started by ghostinthemachine, Oct 20, 2015.

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  1. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    I do BIAB and a small sparge. For a batch requiring 8 gallons of water I mash in 6 gallons and do a t bag sparge in 2 gallons (the last batch i did was 14 lbs of grain in 8 gallons of water). I mash in a 15.5 gallon keggle with a lid. Once I add the grains i cover with a sleeping bag. When I take the temp there is a big difference between the edges and the center of the mash so i stir periodically.

    I use iodine to check conversion. After an hour of mashing the iodine turned black and was still turning black after 2 hours. I used brew cipher to check my effieciency and it was 61%. (1.066 o.g. for dubbel, sugar added as well). I was mashing at 154 degrees, strike water was 162 degrees. I added a gallon of the sparge water (at 170 degrees and stirred it in) at the hour makr to bring the temp up for the next hour.

    Am i having problems because I am using an uninsulated keggle?
     
    #1 ghostinthemachine, Oct 20, 2015
  2. Brew_Betty

    Brew_Betty Initiate (0) Jan 5, 2015 Wisconsin

    Could be a coarse grain crush. Do you crush your own grain?
     
    #2 Brew_Betty, Oct 20, 2015
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  3. GetMeAnIPA

    GetMeAnIPA Pooh-Bah (2,559) Mar 28, 2009 California
    Pooh-Bah

    i get @70 efficiency with my biab. I do full volume, then squeeze the crap out of the bag, hang it over a pot then sparge with like 1/2 gallon to get the last drops.

    As mentioned above I double mill my grains at the LHBS. I know 70% might be kinda low but I can repeat it, which is the key. The last few beers I have brewed I hit my gravity right on or off by .01. If I have to buy an extra pound or two of grains to get my desired ABV it's worth, rather then stressing over some high effienciey number.
     
    #3 GetMeAnIPA, Oct 20, 2015
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  4. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    No, I get the lhbs to double crush my grain through rollers.
     
    #4 ghostinthemachine, Oct 21, 2015
  5. inchrisin

    inchrisin Pooh-Bah (2,013) Sep 25, 2008 Indiana
    Pooh-Bah

    After examining the crush, I'd say that making sure you don't have dough balls, stirring between batches, (if you batch sparge), and water pH are all factors to look into. I've noticed that the finer the crush, the longer I take to dough in when I start mashing. The stuff turns to glue.

    How are you doing your iodine tests?
     
    #5 inchrisin, Oct 21, 2015
    Last edited: Oct 21, 2015
  6. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    I take a sample from outside of the grain bag so i do not get any grain pieces in the sample. I then put a bit on a white plate and drip some iodine into it
     
    #6 ghostinthemachine, Oct 21, 2015
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  7. Seacoastbrewer

    Seacoastbrewer Initiate (0) Jun 5, 2012 New Hampshire

    Maybe a factor of your grain bill? What was in the recipe? Also, try describing your lautering process.
     
    #7 Seacoastbrewer, Oct 21, 2015
  8. dmtaylor

    dmtaylor Savant (1,149) Dec 30, 2003 Wisconsin

    You lose a buttload of heat every time you do that. If you can get the temperature pretty well stabilized in the first 5-10 minutes of the mash to where you are comfortable, and then after that just leave the mash the heck alone, you *might* see better results, maybe. But honestly, I'm just thinking out loud and this is probably not the problem.

    Crush harder. Triple crush if you need to. See if that helps. Seriously.
     
    #8 dmtaylor, Oct 21, 2015
  9. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    When the mash is complete i turn on the heat and let the temp rise for about 10 minutes. i then pull the bag and let it drip. i then put the bag into a bucket and pour 2 gallons of 170 degree water into it. I drain again then set the bag in a large stainless pan and squeeze out any remaining wort.
     
    #9 ghostinthemachine, Oct 21, 2015
  10. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    The way my keggle is cut there is a hole on by the lid and i leave my mash paddle in during mash. i wrap my keggle with a sleeping bag and i can periodically stir without removing the lid or insulation.
     
    #10 ghostinthemachine, Oct 21, 2015
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  11. inchrisin

    inchrisin Pooh-Bah (2,013) Sep 25, 2008 Indiana
    Pooh-Bah

    We can stop pointing a finger at crush until we see a pic. There should be some flour, but it shouldn't be ALL flour. You've made some bigger beers before and without efficiency decreases like this. Right?
     
    #11 inchrisin, Oct 21, 2015
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  12. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    I brewed a stout at 1.062 a couple weeks ago and hit the number i was wanting. I had the same problem and had to mash for an extra hour and a half to get the iodine to not change color. the batch before that i had to add DME. I have been basing my recipes off of 66% mash efficiency. I think next year when I'm out of school i'm going to invest in a mash tun and hlt so i can do full all grains and hopefully be consistent. I'm not worried about not hitting high efficiency...im worried about being inconsistent.
     
    #12 ghostinthemachine, Oct 21, 2015
  13. Seacoastbrewer

    Seacoastbrewer Initiate (0) Jun 5, 2012 New Hampshire

    What was the grain bill for the recipe?
     
    #13 Seacoastbrewer, Oct 21, 2015
  14. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana

    #14 ghostinthemachine, Oct 21, 2015
  15. dmtaylor

    dmtaylor Savant (1,149) Dec 30, 2003 Wisconsin

    66% is not bad efficiency. Long as you're reasonably consistent there, it's not bad at all.

    You might want to stop mashing out at 170 F (heating mash to 170 before dripping). Just the extra few minutes at temperatures below 170 F could increase your efficiency by a couple percent, possibly. Mashout is unnecessary and perhaps detrimental for homebrewers. It's really only needed for the big commercial breweries where it might take hours to get the mash up to a boil. Homebrewers can just "mash out" via bringing the wort to a boil in a matter of minutes after runoff.
     
    #15 dmtaylor, Oct 21, 2015
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  16. GetMeAnIPA

    GetMeAnIPA Pooh-Bah (2,559) Mar 28, 2009 California
    Pooh-Bah

    Try your same process but skip the high volume of sparge water. I feel like you are losing efficiency because you don't have enough water to do the passive sparging that works with biab. By cutting the water by two gallons you are losing efficiency and not making it up with the sparge. I am just going off a hunch but when I do full volume mash I get solid efficiency. At least it's worth a try.
     
    #16 GetMeAnIPA, Oct 22, 2015
  17. HerbMeowing

    HerbMeowing Maven (1,295) Nov 10, 2010 Virginia
    Trader

    After filling the kettle with wort ... put a pinch of the mash on the front of your tongue and suck the juice.
    Is it sweet?
    If so ... you're leaving money on the table ==> low eff.
     
    #17 HerbMeowing, Oct 22, 2015
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  18. ghostinthemachine

    ghostinthemachine Initiate (0) Aug 14, 2015 Louisiana


    here is the catch....my first two batches without the sparge had lower efficiency. i gave away my whole all grain system 3 years ago. big mistake. im going to go back to regular all grain first chance i get. my beer is better now because of the amount of reading and research i do now but at least it was consistently meh before lol. I knew what i was going to hit each time
     
    #18 ghostinthemachine, Oct 22, 2015
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  19. VikeMan

    VikeMan Grand Pooh-Bah (3,067) Jul 12, 2009 Pennsylvania
    Pooh-Bah

    OP's issue is that this batch didn't get 66%. It got 61%. That's what he's concerned about.

    Mashing out is not an efficiency killer. Depending on context, it can even increase efficiency a little, by decreasing the viscosity of the runoff. But I will say that mashing out is something a homebrewer should probably always do or always not do, just because either way, the process consistency eliminates a variable.

    Having said I'll that, I'd be willing to bet that mashing out (or not) has a bigger impact on fermentability than it does on mash efficiency.
     
    #19 VikeMan, Oct 22, 2015
  20. dmtaylor

    dmtaylor Savant (1,149) Dec 30, 2003 Wisconsin

    True. True.
     
    #20 dmtaylor, Oct 22, 2015
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