Refractometer Question

Well…at the polite urging from a few of you, we have taken the plunge and ordered one of these.
Anpro Brix Dual Scale with Auto Temp Corrections for home brewing. It was not expensive, at $19.46 delivered to my front door.

Never used one, so hopefully it is user friendly!

What is the experience of those who use one of these? Good? Bad?

Thanks for the info!

I don’t know about that brand and model. but I find a refractometer to be very useful. You do have to know how to use it and how to correct for the alcohol content of fermenting wort. There are many forum threads about “stalled fermentations” from people who don’t do the correction and think they have a problem when they don’t. I don’t consider it a replacement for a hydrometer, but a supplement. I still use a hydrometer for OG at pitching time and for FG before packaging, but a refractometer is great during mash and during fermentation because the sample volume is so small and there is no need to bring the sample to the proper temperature.

The refractometer works great, but you need to know how to use it properly.  Particularly when alcohol is present, ignore the SG scale and only measure in Brix.  When done right, the calculators are accurate within 0.001 of a hydrometer on almost every reading.  You also need to use the right conversion calculator.  One set of equations is more accurate than another based on the SG…

For gravity above about 1.014, or if in doubt, use the calculator at Brewer’s Friend, which uses the Petr Novotny formula:

For gravity below 1.014, I recommend Sean Terrill’s calculator:

http://seanterrill.com/2012/01/06/refractometer-calculator/

Further references from yours truly (you NEED to read at least the first one if not both):

https://www.homebrewersassociation.org/forum/index.php?topic=28544.15

https://www.reddit.com/r/Homebrewing/comments/bs3af9/sean_terrills_website_issues/

This should be my final guidance for anyone and everyone, forever.  I’ve spent dozens if not hundreds of hours analyzing data.  This stuff will give you super accuracy within 0.001, when done right, with a properly calibrated instrument.

Cheers all.

I use the refractometer during brewday. At the end of the brewday, as I am filling the fermenter I take a hydro sample for OG. I compare the hydro, refractometer, and Tilt to ensure everyone is playing nicely. At the end of fermentation I take another hydro sample to get FG.

I also use my refractometer throughout the boil until I see that I’m getting close to my projected OG.  Then I take a sample and confirm with my hydrometer.  The refractometer is an awesome tool when used properly.  But I always like to confirm critical measures with my hydrometer.

Don’t forget to calibrate your new refractometer.  Mine was off A few points when I unpacked it.

Zero it with distilled water. Use a sugar solution to check vs. a hydrometer. If you are really want to do a deep dive make a 10% sugar solution, it should read 10 Brix. There are many refractometers that have a SG scale that seems off. 9.98 Brix should be 1.040 SG.

Thanks for all f the good advice. We will calibrate with distilled water.
Tomorrow is a big-brew day, so will have a chance to try it out.

I am not a refractometer fan.  I have 4 and none agree with each other or my hydrometer.  I prefer a quality hydrometer and a fast cooling method for the sample.  I can get a 4 oz. sample from boiling to 60F in 30-60 seconds and that’s good enough for me.

I find a refractometer useful in its own right, even if the post-fermentation gravity calculation models aren’t going to be exactly the same as the hydrometer for every style of beer.  If you think in brix, it doesn’t really matter.  For a given recipe, knowing that you generally would hit a certain brix is useful to know, as well as making it very easy to compare to commercial beers without wasting a whole beer to degassing.

This unit gives dual readings, in Brix and SG.

I too have a lot more faith in my 30 year old hydrometer than my refractometer cuz I did some tests with sugar solutions that showed the hydro to be more accurate, the refract reads below actual gravity until around 1.020 and reads higher than actual above ~1.025. The higher the gravity the further off the refract is, but it is still useful for quick reads, and as a doublecheck for those moments when my cranial rectalitus strikes. I started with a cheapo $50 dual scale refractometer and like Dave had to calibrate every freaking time I used it, it quickly wound up in the closet and was replaced by a Vee Gee, that one always reads the same with distilled water - 0.999 at 60*, in 3 years I haven’t had to recalibrate it once.

Yes, but the SG is only valid on unfermented wort.  Alcohol changes the relationship and you have to use a calculator and know the OG to convert to gravity.

How do you do that?

Put a boiling sample in a metal cocktail shaker with the lid on.  Swirl it in a bowl of ice water  Never takes me more than 60 seconds.  It helps that the Brewing America hydrometer I use only needs 4 oz.

Thanks, I’ll give it a shot.  I have an eDrometer, so I don’t need a large sample either.

I rarely care enough to use it, but I acquired a lab grade hydrometer for final gravity readings.  It only has a range of .995 to 1.020, if I recall correctly.  Most of the time the refractometer is sufficiently close for my homebrewing.  I find it interesting, however, how many people who are first tasting a homebrew want to know the ABV and total time from brewing to drinking, but little else about the process.

I have always taken a sample in my hydrometer tube, measured the SG with a hydrometer, then taken a temperature measurement.  I then take both measurements and use the calculation tool in BeerSmith to derive the reading.  Are you suggesting this is not accurate?  I’m wondering why you would need a 60° sample.

My instructions say to take the sample for calibration at room temp, 70 degrees.

Homebrew hydrometers are typically calibrated at 60F.  So any deviation in the sample temp will introduce error.

It sounds like you are already accounting for differences from standard, so your process sounds fine to me.

The only thing you might want to verify is that your hydrometer is actually calibrated to the 60F standard.  It also doesn’t hurt to check the calibration with a 60F pure water.  Those pieces of paper can shift in the glass tube sometimes.

Paul

For one reason, because it’s dangerous to use boiling wort with glass.  For another,the farther away you are from a hydrometers calibration temp, the less accurate the conversipn formula is.  I use a thermos hydrometer, which has a thermometer and correction table built into it.