Using a refractometer to monitor fermentation
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Yes. But alcohol changes the reading significantly and even with correction tables, the refractometer reading tends to not be accurate once fermentation begins. A hydrometer is far more useful for SG readings once fermentation has started.
Mad_Milo
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There are converters online to assist with using a refractometer during/after fermentation. See http://www.onebeer.net/refractometer.shtml for one.
Major advantage of using a refractometer is the minuscule sample you need.
I would guess that the beer is fairly uniform as long as you don't get trub/yeast crud in the sample. Remember the yeast stir up the wort pretty well while fermenting.
Major advantage of using a refractometer is the minuscule sample you need.
I would guess that the beer is fairly uniform as long as you don't get trub/yeast crud in the sample. Remember the yeast stir up the wort pretty well while fermenting.
JDL
Well-Known Member
This explains a lot. I have been using a refractometer for all my brews and I have not been able to hit my final gravity at all and it always ends up high.
I used the calculator on the link above and this is what I came up with, does this sound right.
O.G. before fermentation comes out to 1.046 on a APA mashed at 154 degrees.
F.G. on the refractometer comes out to 1.020 which is way high, that is after a month in the primary with temps never going above 70 and not below 63 with nottingham.
Using a conversion chart, 1.020 in brix should be 5.08.
Using the link above it says my final gravity is actually 1.004. Is this correct? could it of actually gotten this low?
Correct me in my errors please....
Jeff
I used the calculator on the link above and this is what I came up with, does this sound right.
O.G. before fermentation comes out to 1.046 on a APA mashed at 154 degrees.
F.G. on the refractometer comes out to 1.020 which is way high, that is after a month in the primary with temps never going above 70 and not below 63 with nottingham.
Using a conversion chart, 1.020 in brix should be 5.08.
Using the link above it says my final gravity is actually 1.004. Is this correct? could it of actually gotten this low?
Correct me in my errors please....
Jeff
motobrewer
I'm no atheist scientist, but...
Mad_Milo
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Something to keep in mind with refractometers is temperature. Not of the wort/beer but of the device itself. Make sure it's calibrated with distilled water at the room or cellar temperature you usually read at.
I was scratching my head for a few final readings as they were coming in rather high after calcuations. Yet the beer wasn't nearly as sweet as the refractometer suggested. Took the sample and the meter upstairs and let it set for a while, and voila!
Made much more sense compared to the recipe and what I was tasting. My basement was in the upper 50s and I last calibrated the meter at 70F in the spring.
I was scratching my head for a few final readings as they were coming in rather high after calcuations. Yet the beer wasn't nearly as sweet as the refractometer suggested. Took the sample and the meter upstairs and let it set for a while, and voila!
Made much more sense compared to the recipe and what I was tasting. My basement was in the upper 50s and I last calibrated the meter at 70F in the spring.
I don't brew that often so it just makes sense for me to check calibration on my refractometer each time I use it. I've measured against my hydrometer for fermented wort readings the first few times and when using the online, or on my Android phone, conversion utility it's always been dead on.
smizak
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I wish that was the case with mine. It will read dead-nuts on with a sugar solution, the second you try wort, it's all over the place. Like +/- 20% of a hydrometer reading for different batches. Completely useless to me.
