Refractometer consistency

Discussion in 'Brewer's Friend Announcements' started by Tal Orbach, Nov 18, 2018.

  1. Tal Orbach

    Tal Orbach Member

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    Weird thing,
    I had a batch of wort which I started fermenting in 2 different vessels (in the same fridge - so conditions where effectively the same).
    After a few days, one of them gave me a refractometer reading of 5.5 Brix, and the other was 6.1 (took several readings of both - these numbers remained consistent throughout the readings).
    However, When I took a hydrometer reading, both presented a gravity of 1.013.
    So, the gravity is the same, but the Brix reading is different. The only explanation I could think of for this is different ABV or something, but why would that be the case, if they fermented in similar conditions? (one of the containers was open, but it was at 18C, so I don't think there was a lot of alcohol evaporation going on)

    Any thoughts?
     
  2. White Haus Brews

    White Haus Brews Active Member

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    Hmm how strange. I wouldn't think alcohol evaporation would be the case since that would show up with the hydrometer as well. I'm assuming yes but they were both tested at the same temperature, right? Did one fermenter get more kettle trub? Or dry hopped differently? I wouldn't think either of those would matter too much but just thinking out loud. What was the OG Brix by chance?
     
  3. Tal Orbach

    Tal Orbach Member

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    Yeah
    I don't think so.
    No dry hopping at all (or anything of that sort)
    I didn't take a Brix reading prior to fermentation, but the hydrometer showed 1.050
     
  4. White Haus Brews

    White Haus Brews Active Member

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    If you go with that OG your brix was around 12.5 which based on the refractometer calculator your corrected FG on each fermenter was 1.005 and 1.009 which are obviously not only different than each other but way considerably off your hydro.

    Seems like somethings up with your refractometer. Have you tested them side by side in the past? Less likely the hydrometer since at least that's consistent but have you made sure it sits at (or at least near) 1.000 in water?
     
  5. Tal Orbach

    Tal Orbach Member

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    From what I've read, every refractometer has some correction factor, which needs to be calculated, no?
    Anyway, I haven't really figured out mine yet, but I guess with the correction factor, one of these readings could work to match the hydro.

    I check the refractometer with water every time I use it. It's always on 0. Never needed any calibration...
     
  6. White Haus Brews

    White Haus Brews Active Member

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    Yeah fair enough. Yes every refractometer has it's own correction factor and it might help a little but seeing 2 different results from the same gravity wort isn't confidence inspiring :p
     
  7. Tal Orbach

    Tal Orbach Member

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    I agree. That was exactly my problem.
    The problem is that while it seems that my refractometer is very consistent when the sample comes from the same vessel (nevermind beer, wort or water), it's no longer the case when I switch to a different vessel, even though the gravity reading remains the same. That's exactly my point. :/
     

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