Hello all,
I've got an Plinian Progeny extract (northern brewer) in progress. Brewed on 9/25. Today is 10/15. Measured SG with Brix refractometer at 20, which calculated to 1.083. Instructions say it should be 1.090 so it's close. It is in the basement around 65 degrees, and I used two packets of US-05. I made a starter with one of the packets because I have a stir plate and had some Fast Pitch as well. The other packet I threw in dry at the same time. It's a 6 gallon batch so I used a blow off tube, but seemed to fermenet as expected, for several days. Nothing came out of the blow off. I replaced that with a normal airlock after it calmed down.
Last night I measured again, and it showed 13.5 brix with the rafractometer. My calculator shows that as 1.037. So I thought it might be stuck. Today I read they can be inaccurate for FG, so this morning I used a hydrometer. It showed 1.026. The hydrometer also has a brix scale on it which showed 7.5. If I use a calculator with 1.026, it's about 7.5% ABC. But if I do the calculator on brewersfriend with 1.083 starter, and 7.5 brix now, it's showing 10% and that would be done. So I'm a little confused as to which number to use and if this batch is good or has a problem..
I did taste it, seems great but I can't really tell if it's "Sweet" or not..
Thanks for the help!
As long as the hydrometer is working as it should, and calibration was checked/verified with distilled water at it's calibration temp (usually 60°F, but may differ), it will give you the most accurate reading. Especially once fermentation has started and alcohol is produced. Alcohol presence skews a refractometer reading due to alcohol having a much higher refractive index, hence using the correction formula. But a slight deviation or misreading of the fairly short scale can make a relatively large difference.
You can use either Brix or SG scales on a hydrometer, whatever which you're most comfortable or gives you the readout on the scale you want to use.
For all security, double check that the Brix and SG scales are correctly correlated on the printed scale.
My emphasis in bold/red ^ that would be an incorrect conclusion.
You need to use either Brix/Plato or SG for both entries. You can't mix those on that calculator. So OG is 1.083, current SG is 1.026 ==> ABV 7.48%
Now with a current gravity of 1.026 your beer may or may not be quite finished.
Especially in higher gravity/higher alcohol beers, the last few 5-10 points can take much longer than the 50-60 points before, as the more complex sugars take longer to convert (to alcohol), while the alcohol is inebriating the yeast.
I'd leave it for another 2 weeks at around 70-72F to ferment/condition out, then take another reading with your hydrometer. If it matches your today's reading of 1.026, it's probably as done as it will be.
Post time 2022-10-15 10:30:02