Refractometer?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

HawksGirl

Member
Joined
Jan 29, 2011
Messages
17
Reaction score
1
Location
Surprise
So I actually have a nice reef aquarium. While my boyfriend was using the hydrometer, I mentioned, my refractometer measures specific gravity of my salt tank. Will this work for brewing as well? The main reason I ask is that we got a reading of 1025 on the glass "brewing" hydrometer and my refractometer read 1035, so maybe not as accurate? This reading was post fermntation.
 
It most definitely will. It's perfect for taking OG readings of the wort providing there's an ATC on the refractometer, but there's also some math you can do to compensate for the temp it was taken at.

Additionally, it can be used for taking FG readings as well, using some formulas to compensate for the now new alcohol content of the wort/beer.

Check out the spreadsheet at morebeer.com. http://morebeer.com/learn_vids/vids_refract

Links are just below the video!

edit: I should also add that using the hydrometer as well just to compare results would not be a bad idea :)

Hope this helps!
 
A refractometer reading gets skewed by the alcohol, that's why the reading was off. If you use the morebeer spreadsheet linked above you'll be A-OK!
 
It most definitely will. It's perfect for taking OG readings of the wort providing there's an ATC on the refractometer, but there's also some math you can do to compensate for the temp it was taken at.
Snip....

The ATC corrects for the air temperature the refractometer is subjected to, not for the sample. The scale in the refractometer "floats" on a bi-metal wire, same principle as bi-metal thermometers. It is a narrow correction range however so I always leave my refractometer in the house in both hot and cold weather extremes of the current season. This information came from the Basic Brewing podcast dated Sept. 2, 2010 (visit www.basicbrewing.com to listen)

The hot wort sample is no more than 1/2 teaspoon so it quickly cools on the refractometer lens and is not an issue.
 
So I actually have a nice reef aquarium. While my boyfriend was using the hydrometer, I mentioned, my refractometer measures specific gravity of my salt tank. Will this work for brewing as well? The main reason I ask is that we got a reading of 1025 on the glass "brewing" hydrometer and my refractometer read 1035, so maybe not as accurate? This reading was post fermntation.

Is the refractometer designed to measure sugar or salt in solution? If it's designed to measure salinity, I'm not sure you'll get an accurate brix reading.
 
Is the refractometer designed to measure sugar or salt in solution? If it's designed to measure salinity, I'm not sure you'll get an accurate brix reading.

I believe a refractometer just measures density of the fluid, whether it be a result of sugars, salts, or whatever else that can dissolve in it.

Someone correct me if I'm wrong since I only just started using a refractometer recently.

EDIT: I'm probably wrong...Google is my friend...
 
I believe a refractometer just measures density of the fluid, whether it be a result of sugars, salts, or whatever else that can dissolve in it.

Someone correct me if I'm wrong since I only just started using a refractometer recently.

EDIT: I'm probably wrong...Google is my friend...

A hydrometer measures a fluid's density. A refractometer measures the bending of light when passing through a substance. I'd think light would refract differently with sugar and salt.

OP: Alcohol will distort a refractometer's reading, but it may or may not be the only source for the discrepancy. Sugar refractometers are a dime a dozen on ebay. I'd recommend him getting one specific for brewing applications.

Have a look at Bobby_M's video discussing the differences in process between the hydrometer and refractometer.:mug:

 
Last edited by a moderator:
I noticed this weekend that Brewzor on my phone has a Refractometer adjustment tool. Might have to use it outside of brew day and see how accurate that tool is. Allows you to select from unfermented wort, fermenting wort, or finished beer.
 
The ATC corrects for the air temperature the refractometer is subjected to, not for the sample. The scale in the refractometer "floats" on a bi-metal wire, same principle as bi-metal thermometers. It is a narrow correction range however so I always leave my refractometer in the house in both hot and cold weather extremes of the current season. This information came from the Basic Brewing podcast dated Sept. 2, 2010 (visit www.basicbrewing.com to listen)

The hot wort sample is no more than 1/2 teaspoon so it quickly cools on the refractometer lens and is not an issue.

Ah ok, thanks for the correction.
 
Back
Top