Choosing a refractometer - Page 2

ILuvIPA · 11-25-2010, 05:54 PM

beninan, it's not intended to replace your hydrometer but supplement it. It allows quick check at the brew pot using a very small sample.

I went AG recently and quickly found it's a PITA to check OG of hot runnings, check my OG after sparge, etc. Using my hydrometer I have to pull a several ounce sample, ice it in a water bath. . .dreaming of doing those tasks in seconds with a couple drops of wort. I'll still use my hydro to verify OG into and out of the fermenter.

EDIT: sorry all, I was too slow on the trigger. . .

giligson · 11-25-2010, 07:34 PM

Yes, once alcohol gets into the mix then the refractive index changes considerably and will give you a falsely "dense" reading.

The first 3 brews I used it on I was very paranoid about equivalency with my hydrometer so I would take samples on both instruments - every time, the refractometer was dead on. Now I don't even bother to take a gravity sample on brewday. It is a godsend when you want to track your SG near the end of your sparge and especially if you need to adjust your preboil SG by adding water to your wort (so as to get the hops utilization correct). No more waiting on an icewater bath to cool your sample to reading temp.

And for those of you who say - "just use a correction factor to read your hydrometer at a higher temp" - I have already tossed one hydrometer into the trash bin after popping it into hot wort and having the glass crack.

Catt22 · 11-25-2010, 07:49 PM

Quote:

Originally Posted by AZ_IPA

you can calibrate it to 1.000 (or 0 brix) using distilled water

You can also calibrate it with tap water.

beninan · 11-26-2010, 01:02 AM

Quote:

Originally Posted by Catt22

You can also calibrate it with tap water.

I do have a refractometer (for automotive coolant use to check the antifreeze-to-water concentration) and I do know that tap water is not the best choice to calibrate with due to the impurities in the water. I guess depending on how clean your water is, it would be better than no water at all.

Catt22 · 11-26-2010, 03:59 AM

Quote:

Originally Posted by beninan

I do have a refractometer (for automotive coolant use to check the antifreeze-to-water concentration) and I do know that tap water is not the best choice to calibrate with due to the impurities in the water. I guess depending on how clean your water is, it would be better than no water at all.

Nonsense. Unless you happen to have really, seriously phukked up tap water there will be no discernible difference. Do you really think that your water contains enough sugar, or whatever, to register on our very crude refractometers? Additionally, if it's only impurities such as mineral content that you are referring to, and if you are brewing with this water, you would want to calibrate this water to zero out with the impurities included. That way, you would be measuring only the sugar contributed by the mashing process and not the sum total of the impurities plus the sugars. Obviously, you can't go wrong using distilled water for the calibration, but it really isn't at all a necessity. You can easily confirm this with a simple unbiased test using each. The key word here being "unbiased". IOW, it would be best to eliminate preconceived notions. What's the Brix reading of your tap water? Mine reads 1.000 as best I can tell using my cheapo Chinese made refractometer.

beninan · 11-26-2010, 08:39 PM

Quote:

Originally Posted by Catt22

Nonsense. Unless you happen to have really, seriously phukked up tap water there will be no discernible difference. Do you really think that your water contains enough sugar, or whatever, to register on our very crude refractometers? Additionally, if it's only impurities such as mineral content that you are referring to, and if you are brewing with this water, you would want to calibrate this water to zero out with the impurities included. That way, you would be measuring only the sugar contributed by the mashing process and not the sum total of the impurities plus the sugars. Obviously, you can't go wrong using distilled water for the calibration, but it really isn't at all a necessity. You can easily confirm this with a simple unbiased test using each. The key word here being "unbiased". IOW, it would be best to eliminate preconceived notions. What's the Brix reading of your tap water? Mine reads 1.000 as best I can tell using my cheapo Chinese made refractometer.

I see your point, especially if you are brewing with this water. Maybe a more accurate calibrating medium would be the water you brew with. Although like you said, you probably wont have any difference in the reading unless you have an insane refractometer, but then again the little difference in the reading probably would be so minimal it wouldn't mater.

Catt22 · 11-27-2010, 04:42 AM

Quote:

Originally Posted by beninan

I see your point, especially if you are brewing with this water. Maybe a more accurate calibrating medium would be the water you brew with. Although like you said, you probably wont have any difference in the reading unless you have an insane refractometer, but then again the little difference in the reading probably would be so minimal it wouldn't mater.

Yeah, any variance should be quite small and of little consequence for brewing purposes. I only use the refractometer to get a fast approximate handle on the gravity anyway, then use a hydrometer for a more precise OG just prior to pitching. I'm never much concerned about an OG gravity point or two variance from my target. I check my refractometer calibration now and then, but I haven't had to adjust it at all so far and I've been using it for quite a long time. I do take care not to handle it roughly or drop it. One tool I like a lot is a long hydrometer which has wider gradations which makes it much easier to read. IIRC, I bought it from William's Brewing and it wasn't very expensive. I got really tired of squinting at the shorter one.

dbsmalls · 04-13-2011, 02:24 PM

So I've looked at 1000 different refractometers on eBay. I would really like one with a brix and SG scale along with a hard storage case. I cannot seem to find this combo for a reasonable price. I've found brix only with a hard case for about $20. I've found brix and SG combo with a soft zipper case for about the same price. The only combo scale with a hard case is $65. Is it even worth it for the SG scale?

giligson · 04-13-2011, 09:39 PM

definitely not worth the $ for another scale. Get a Brix to SG conversion scale on the net, print it out and post it up in your "brewery". After a while the Brix becomes as intuitive as the SG anyways.