Gravity Gravitas

[antiphile]

After a successful brew day last week, I'm now firmly re-ensconced in the Australian hothouse called Brisvegas. But that's all the whinging to be done this hour.

 

I finally bit the cruise missile and bought myself a refractometer, and I'm trying to work out why it took me all this time. It made brew day an absolute breeze, and meant I was getting absolutely reliable, exactly reproducible and very accurate results all through the entire process. From samples of boiling wort, mash tun samples, second runnings, and fermenter OGs (and ultimately FGs) it was incredibly quick and easy. No batteries or power source needed (unlike some other personal devices), very easy to read for those of us with eyes that don't work as well as they use to (and I'm not going to spell out what may have contributed to that), and for less than $50. And it has automatic temperature compensation (ATC), but that only works between 10 and 30 degrees C.

 

Need an SG from boiling wort, take half a teaspoon of stirred liquid, leave for a minute to cool to room temp, add 2 or 3 drops using the supplied pipette, and voila! I reckon it's the ant's pants for all levels and types of brewers.

 

I got mine online from Barleyman (Sydney), but I think they are the same as the ones from Keg King (Melbourne).

 

When I think of how many glass hydrometers my boys and I have broken, and my concerns with some other types I've used and own, it really was an easy slam dunk. Just a personal opinion of course, but it may be worth considering.

 

Cheers

 

Edit: I just noticed what you meant, BL, and corrected "bout" to "bought". Still, I spose it could have been worse: bort or bawt maybe.

[Beerlust]

Hi P2.

 

Nice to see you putting that... "collage" education of yours to some good use!

 

 

I hope your brewing is going well.

 

Cheers,

 

Anthony.

[Hairy]

Phil, have you used it on fermented beer or just unfermented wort?

 

I'm not an expert but I believe you need to make some mathematical changes to the result if you use it on liquid containing alcohol.

 

I will eventually add one to my collection of equipment too.

 

[antiphile]

Ahhh, OK. I haven't used it yet for any fermented wort or for FGs etc. But I will do some research and see what I can find. Thanks for the heads up, mate.

[antiphile]

Found the info you to which you were referring, Hairy, at HomeBrewStuff. It looks simple enough to make the compensation calculation.

 

I can just add another column to my brew batch spreadsheet, or it's probably simpler just to do the conversion in my head.

 

Formula for compensation of ethanol effect on refractometer:

 

SG=1.001843-0.002318474(OB)-0.000007775(OB^2)-0.000000034(OB^3)+0.00574(AB) +0.00003344(AB^2)+0.000000086(AB^3)

 

SG = Specific Gravity, OB = Original Brix, AB = Actual Brix (Brix Readings During Fermentation)

[antiphile]

I finally removed my digit and changed the Batch spreadsheet so (after the OG is recorded by use of a hydrometer) recording of SG can be done by refractometer or hydrometer.

 

I'm guessing it's really only of interest to me, but if anyone else is silly enough to try it, it can be downloaded from here.

 

Notes:

• 
  There are 2 compulsory inputs viz., the brew name or code or both in the first large box, and the date of the brew (or more accurately, the date of pitching for no-chillers).
  

• 
  If both hydrometer and refractometer readings are done for any day, the hydrometer reading takes precedence. The only daily input required is Day 0 (ie. OG) though FG is also recommended obviously. any others are your choice.