Refractometer

[Jtk78]

I'm looking to add a refractometer to my brewing equipment. Seems less likely to break than a hydrometer, don't have to chill a pre-boil sample, lower chance of burns getting a pre-boil sample (did that once already), and less to clean. I understand that once fermentation starts, the hydrometer is a better option. I hear there are calculators to use the refractometer after fermentation, but not sure how accurate they are?

Here's my real conundrum though. I'm looking for a dual gauge with ATC. I have looked at various ones, and they usually show a picture of the number lines. I've seen brix to sg numbers all over the board, and they rarely line up with the conversion charts I've seen. I've seen 15 brix at 1.057 to 1.067, and conversion charts claiming 1.061. What's correct? Do I use the brix side of the refractometer and have a chart handy use?

 

[RM-MN]

What is your purpose for taking the sample? I use preboil as a way to check that I have full conversion and to check on my efficiency. I also take a reading (usually) when the wort is ready to go into the fermenter. My refractometer is a dual scale and I only read the gravity scale and mine is very close to what I get when using the hydrometer.

Post fermentation the reading of the refractometer is skewed because of the alcohol in the beer. If you "need" a totally accurate reading, use the hydrometer. If you can be satisfied with a close approximation there are calculators that will get you quite close. If all you care about is to see that your fermentation didn't stall and is finished, the refractometer reading, although skewed, will tell you as the exact reading isn't as important as the lack of change in the reading.

 

[Jtk78]

RM - I will most likely use my hydrometer for post fermentation, but would use the refractometer for pre-boil, and before going into the fermenter. I've just yet to see a refractometer where the brix to sg scale matches that of the online charts I've seen. And I've seen refractometer with varying scales between models, though still brix to sg. I'll try to post some examples.

 

[Jtk78]

https://www.amazon.com/dp/B01APP1EXG/?tag=skimlinks_replacement-20

This shows a brix 15 at 1.067



https://www.morebeer.com/products/refractometer-dual-scale-atc.html?site_id=5

This one shows a brix of 15 at 1.057



https://www.brewersfriend.com/brix-converter/

This conversion calculator gives a brix of 15 at 1.061.


Which is correct?

 

[fun4stuff]

I'm looking to add a refractometer to my brewing equipment. Seems less likely to break than a hydrometer, don't have to chill a pre-boil sample, lower chance of burns getting a pre-boil sample (did that once already), and less to clean. I understand that once fermentation starts, the hydrometer is a better option. I hear there are calculators to use the refractometer after fermentation, but not sure how accurate they are?

Here's my real conundrum though. I'm looking for a dual gauge with ATC. I have looked at various ones, and they usually show a picture of the number lines. I've seen brix to sg numbers all over the board, and they rarely line up with the conversion charts I've seen. I've seen 15 brix at 1.057 to 1.067, and conversion charts claiming 1.061. What's correct? Do I use the brix side of the refractometer and have a chart handy use?

The SGs listed on the refractometer aren’t accurate. Brix/sg relationship is not linear. The brix/sg conversion listed on those refractometer is based on grapes / wine, not grains/beer. Just use brewersfriend calculators to convert brix to s.g.. (https://www.brewersfriend.com/refractometer-calculator/). You can further increase accuracy by determining your wort correction factor (https://www.brewersfriend.com/how-to-determine-your-refractometers-wort-correction-factor/).

Once you figure out your wort correction factor your refractometer will be very similar to your hydrometer... frequently within a few percent. For awhile I used both a hydrometer and refractometer for every measurement. I found them so close, I ditched by hydrometer. E.g. I’d get an sg of 1.052 and an abv of 5.2% with my refractometer and 1.051 /5.1% with my hydrometer. They were almost always 1-3 points from each other over 20+ brews.

Now I only out of hydrometer if I get a reading on refractometer that doesn’t make sense/ far from what I was expecting. I really just want to know 1) am I close to predicted og and 2) am I close to predicted fg? I don’t obsess over a few gravity points.

Note: even if you get one with ATC, you’re still going to want to let it get close to room temp (temp you calibrated it to). Often times I’ll give the dropper 30 secs to cool down (time it takes me to walk inside to get refractometer). Then placing a small drop on the room temp refractometer brings temp down the rest of the way.

 

[fun4stuff]

https://www.amazon.com/dp/B01APP1EXG/?tag=skimlinks_replacement-20

This shows a brix 15 at 1.067



https://www.morebeer.com/products/refractometer-dual-scale-atc.html?site_id=5

This one shows a brix of 15 at 1.057



https://www.brewersfriend.com/brix-converter/

This conversion calculator gives a brix of 15 at 1.061.


Which is correct?

https://www.brewersfriend.com/2013/...rrectly-for-maximum-accuracy-in-home-brewing/

“IGNORE the SG scale if your model has it – only pay attention to the Brix scale. The relationship between Brix and SG is not linear!”

 

[balrog]

I've seen ATC refracts that attempt to remove the "wort correction factor" so that reading the BRIX side and the online calcs or Beersmith, converts to what the ATC's SG side says with wort correction factor of 1.000 not the supposed standard of 1.040.

Anyway, as others have said, read Brix only. Never trust the SG side in the refractometer. Use a calc to convert. Also, I suggest calibrating occasionally with clean water for 1.000 and making a known SG solution with table sugar (google) and check with refrac.

 

[Jtk78]

https://www.brewersfriend.com/2013/...rrectly-for-maximum-accuracy-in-home-brewing/

“IGNORE the SG scale if your model has it – only pay attention to the Brix scale. The relationship between Brix and SG is not linear!”

Thank you for this link as well as the one in your previous post. I have bookmarked both of these for later reading before I order something. I have no problem ignoring the sg scale and using a conversion calculator. My main concern is the accuracy even on the brix side.

 

[Jtk78]

.......

Anyway, as others have said, read Brix only. Never trust the SG side in the refractometer. Use a calc to convert. Also, I suggest calibrating occasionally with clean water for 1.000 and making a known SG solution with table sugar (google) and check with refrac.

Thank you. I will look up a sg solution to calibrate as well.

 

[fun4stuff]

Thank you. I will look up a sg solution to calibrate as well.

I believe it’s better to use a light dry malt extract rather than table sugar. You want to use a solution to calibrate that’s similar to what you’ll be measuring. Relationship of Refraction and brix will vary with table sugar, grains, grapes, etc. you can also increase accuracy by calibrating with a solution that is close the OGs of beers you usually use. For example, if you always brewed light colored beers with an OG of 1.050, you’d get the most accurate results if you determined your wort correction factor from 1.050 solution made from light Pilsen dry malt extract.

In my case, I almost always make light colored beers that are between 1.040 and 1.060. So Several of my data points that I used to determine my wcf are from solutions of light Pilsen dme that are around 1.050. I have made some big beers (1.080+) where I had to pull out my hydrometer to get a more accurate reading.

It’s not as important that the brix scale on you’re refractometer is 100% accurate. It often times won’t be (it was made for using with grape juice) which explains the variability you see. It’s doesn’t matter as long as you use the same refractometer , calibrated to 1.000 before each use, at a similar temp, and use a WCF that’s specific to your refractometer to convert the brix from your refractometer to SG.

 

[dmtaylor]

The SG numbers are all wrong. Only use the Brix numbers. I repeat: Only use the Brix numbers!

 

[hawkbox]

Damn it! Now I need to go back and recalculate everything.

 

[RM-MN]

The SG numbers are all wrong. Only use the Brix numbers. I repeat: Only use the Brix numbers!

My SG numbers match my hydrometer readings nearly exactly. They aren't all wrong.

 

[RM-MN]

https://www.amazon.com/dp/B01APP1EXG/?tag=skimlinks_replacement-20

This shows a brix 15 at 1.067



https://www.morebeer.com/products/refractometer-dual-scale-atc.html?site_id=5

This one shows a brix of 15 at 1.057



https://www.brewersfriend.com/brix-converter/

This conversion calculator gives a brix of 15 at 1.061.


Which is correct?

It looks like you just proved that the calculators are all wrong.

Note: even if you get one with ATC, you’re still going to want to let it get close to room temp (temp you calibrated it to). Often times I’ll give the dropper 30 secs to cool down (time it takes me to walk inside to get refractometer). Then placing a small drop on the room temp refractometer brings temp down the rest of the way.

With my refractometer I drip one or two drops of hot wort on the plate and flop the cover on. That spreads the wort out into a very thin layer which cools very rapidly. I never wait for it to cool. If I wanted to wait, I'd just use the hydrometer.

 

[doug293cz]

I believe it’s better to use a light dry malt extract rather than table sugar. You want to use a solution to calibrate that’s similar to what you’ll be measuring. Relationship of Refraction and brix will vary with table sugar, grains, grapes, etc. you can also increase accuracy by calibrating with a solution that is close the OGs of beers you usually use. For example, if you always brewed light colored beers with an OG of 1.050, you’d get the most accurate results if you determined your wort correction factor from 1.050 solution made from light Pilsen dry malt extract.

In my case, I almost always make light colored beers that are between 1.040 and 1.060. So Several of my data points that I used to determine my wcf are from solutions of light Pilsen dme that are around 1.050. I have made some big beers (1.080+) where I had to pull out my hydrometer to get a more accurate reading.

It’s not as important that the brix scale on you’re refractometer is 100% accurate. It often times won’t be (it was made for using with grape juice) which explains the variability you see. It’s doesn’t matter as long as you use the same refractometer , calibrated to 1.000 before each use, at a similar temp, and use a WCF that’s specific to your refractometer to convert the brix from your refractometer to SG.

I strongly disagree. If you want the Brix to SG calculators to work correctly, you need to make sure that your Brix scale is reading correctly, and the Brix scale is defined for sucrose (table sugar.) So, you want to calibrate with sucrose solutions, and then determine the wort correction factor suitable for your worts. Any decent calculator will allow you to supply your own wort correction factor. 15°Brix is equivalent to a 1.061 SG sucrose solution. If your wort correction factor is 1.04 (a typical value) then 15°Brix corresponds to a wort SG of 1.059. With a wort correction factor of 0.96, 15°Brix corresponds to a wort SG of 1.064.

Brix is defined as the weight % sucrose in a sucrose/water solution. So, a 10°Brix solution can be made by mixing 1 part by weight sucrose with 9 parts by weight distilled or RO water. A 15°Brix solution is 1.5 parts sucrose and 8.5 parts water, and a 20°Brix solution is 2 parts sucrose and 8 parts water. These solutions should have SG's of 1.0400, 1.0611, and 1.0830 respectively.

This link explains how to calculate your wort correction factor.

Edit: Or, you could build your own "My refractometer reading to wort SG" calculator by taking both refract and hydrometer readings on lots of different worts, and then using a spreadsheet to determine a correlation equation.

Brew on

 

[Jtk78]

It looks like you just proved that the calculators are all wrong.

I didn't really prove anything. Just caught a variable across 3 different data points. Perhaps the calculator is right and these 2 refractometer are wrong. Although, it seems I have some more reading to do on the matter.

With my refractometer I drip one or two drops of hot wort on the plate and flop the cover on. That spreads the wort out into a very thin layer which cools very rapidly. I never wait for it to cool. If I wanted to wait, I'd just use the hydrometer.

Right! Part of my goal is to not have to wait (as long) to get a reading. Particularly on a pre-boil sample. It would take awhile for my hydro sample to cool, with the jar stuck in ice water.

 

[balrog]

...I drip one or two drops of hot wort on the plate and flop the cover on. That spreads the wort out into a very thin layer which cools very rapidly. I never wait for it to cool.

...Or, you could build your own "My refractometer reading to wort SG" calculator by taking both refract and hydrometer readings on lots of different worts, and then using a spreadsheet to determine a correlation equation.

^This, or rather, these. Both. Very good. Yay. Carry on.

 

[Jtk78]

I strongly disagree. If you want the Brix to SG calculators to work correctly, you need to make sure that your Brix scale is reading correctly, and the Brix scale is defined for sucrose (table sugar.) So, you want to calibrate with sucrose solutions, and then determine the wort correction factor suitable for your worts. Any decent calculator will allow you to supply your own wort correction factor. 15°Brix is equivalent to a 1.061 SG sucrose solution. If your wort correction factor is 1.04 (a typical value) then 15°Brix corresponds to a wort SG of 1.059. With a wort correction factor of 0.96, 15°Brix corresponds to a wort SG of 1.064.

Brix is defined as the weight % sucrose in a sucrose/water solution. So, a 10°Brix solution can be made by mixing 1 part by weight sucrose with 9 parts by weight distilled or RO water. A 15°Brix solution is 1.5 parts sucrose and 8.5 parts water, and a 20°Brix solution is 2 parts sucrose and 8 parts water. These solutions should have SG's of 1.0400, 1.0611, and 1.0830 respectively.

This link explains how to calculate your wort correction factor.

Edit: Or, you could build your own "My refractometer reading to wort SG" calculator by taking both refract and hydrometer readings on lots of different worts, and then using a spreadsheet to determine a correlation equation.

Brew on

I'm actually modifying the brewers friend to show a corrected Brix number. I will then use that to get my hydrometer reading after I have some data points.

This all brings up a slightly different question. I understand I will need some of my own data points to start to get to a pattern for the correction factor. Should there be any predictable patterns though, i.e. darker worts = bigger correction factor, more flaked grains = bigger correction factor? Or is more of a hardware thing in that my refractomter may show a 1.01 correction factor over 20 samples, and your shows 1.04?

 

[BeardedBrews]

So, you want to calibrate with sucrose solutions, and then determine the wort correction factor suitable for your worts.

The calibration vs correction gets confusing.

Calibration - Does the instrument read 15 Brix when I put a known 15 Brix on it? Use Sucrose for this.

Correction(Conversion) - If I put 1.060 wort on the instrument and read the Brix does my conversion calculator give me 1.060? Use Wort for this.


Check your calibration first so you know the instrument works, then figure out your correction factor so that you know your calculator will work.

 

[dmtaylor]

This all brings up a slightly different question. I understand I will need some of my own data points to start to get to a pattern for the correction factor. Should there be any predictable patterns though, i.e. darker worts = bigger correction factor, more flaked grains = bigger correction factor? Or is more of a hardware thing in that my refractomter may show a 1.01 correction factor over 20 samples, and your shows 1.04?

Great question. I have only used my refractometer for one year, maybe a half dozen batches so far, but I have not noticed any patterns like you mention.

I have determined that the correction factor for my refractometer is 0.98-0.99. Seems odd because it is slightly less than 1, not greater, but compared to my hydro that's what I get.

As such I do believe the correction factor is very specific to each gauge. Some could be 0.95, some 1.06, but all probably somewhere in that range.

The more measurements I make, the closer I get to figuring out whether it's really 0.98 or 0.99 or maybe 0.985.

One other thing worth mentioning, and Sean Terrill will say the same thing, is that the refractometer calculators are not very accurate for very high gravity, high alcohol beers that start above about 1.075 or so and approach 8% ABV or more. On my last imperial brown ale of about 9% ABV, three different calculators all said my final gravity (based on conversion from Brix) should be 1.026-1.031, but my hydrometer (the REAL answer) gave 1.023. So the higher you go, the less accurate any calculators will be. Just be aware of that.

 

[portguy]

My hydrometer is always in synch with my cheap refractometer:
Last batch gave me 12,4 brix post boil, that was the expected 1.050 OG my hydrometer gave.
Even during fermentation with wort correction factor of 1.0, it gives me the same readings. So i just use it for all my readings, and come bottling day i take my only hydrometer reading after fermentation starts nowadays ( some beer ends up wasted anyway, might as well get a reading) So i use both only after the boil and come bottling day. There is always wort and beer that would end up wasted anyways in both these moments.

 

[Nebraskan]

Well, my 2 cents worth.... I have a refractometer that reads both brix and S.G. Brix and Plato being the same. use 10g measured sugar (not malt extract) disolve in about 80ml of deionized water or distilled water, then put into 100ml volumetric flask and fill to the line (100ml) Invert several times and allow to be at 60 deg F. Read that with you refractometer and "correct" it to read 10.0 I have seen refractometer readings that were calibrated with water at 0 to be off by the time you measure grape juice by 2 Brix, usually under. This way it is calibrated to exactly 10.0 Brix. This should give you a lot closer reading. Also, I have found hydrometers that were off, that were professional quality (for wineries). We have 3 that I use the most in the lab, 24-16, 16-8 and 8-0 and also one that is +5 to -5 when we read wines that have gone dry as they will be in the negative Brix.

 

[doug293cz]

Well, my 2 cents worth.... I have a refractometer that reads both brix and S.G. Brix and Plato being the same. use 10g measured sugar (not malt extract) disolve in about 80ml of deionized water or distilled water, then put into 100ml volumetric flask and fill to the line (100ml) Invert several times and allow to be at 60 deg F. Read that with you refractometer and "correct" it to read 10.0 I have seen refractometer readings that were calibrated with water at 0 to be off by the time you measure grape juice by 2 Brix, usually under. This way it is calibrated to exactly 10.0 Brix. This should give you a lot closer reading. Also, I have found hydrometers that were off, that were professional quality (for wineries). We have 3 that I use the most in the lab, 24-16, 16-8 and 8-0 and also one that is +5 to -5 when we read wines that have gone dry as they will be in the negative Brix.

This calibration method is WRONG!. 100 ml of solution will not have a weight of 100 grams unless the SG is 1.000. You have to weigh both the sucrose and the water, you cannot make up to a volume in a volumetric flask. Brix and Plato are weight % (weight/weight), not weight/volume. The difference is significant. For accurate Brix calibration you must use the method I described in post #15.

Brew on

 

[Nebraskan]

Brix is the % of dissolved sugar in solution. Since if you dissolve 10 grams of sugar in about 100ml of water you should have a 10% solution, so to be closer, you use a volumetric flask of 100ml. This flask will have an etched line in the long neck that indicates where 100ml is (at the bottom of the meniscus) in that particular flask. Sugar added to water adds volume. We have to take that into account when we chapitalize, as there is extra volume (gallons of juice) from the added lbs of sugar. I measured out 10g of sugar in 100ml of water at home just now, and at 60 deg my hydrometer floats at the 10 Brix mark. It's not exact, as I said, because I don't have a volumetric flask at home. I have several at my lab in the winery, though. This link shows that if you have 10 Brix, you have 103.98 grams/L of sugar 1L = 1000 ml link: https://vinoenology.com/calculators/fermentation/

 

[fun4stuff]

I strongly disagree. If you want the Brix to SG calculators to work correctly, you need to make sure that your Brix scale is reading correctly, and the Brix scale is defined for sucrose (table sugar.) So, you want to calibrate with sucrose solutions, and then determine the wort correction factor suitable for your worts. Any decent calculator will allow you to supply your own wort correction factor. 15°Brix is equivalent to a 1.061 SG sucrose solution. If your wort correction factor is 1.04 (a typical value) then 15°Brix corresponds to a wort SG of 1.059. With a wort correction factor of 0.96, 15°Brix corresponds to a wort SG of 1.064.

Brix is defined as the weight % sucrose in a sucrose/water solution. So, a 10°Brix solution can be made by mixing 1 part by weight sucrose with 9 parts by weight distilled or RO water. A 15°Brix solution is 1.5 parts sucrose and 8.5 parts water, and a 20°Brix solution is 2 parts sucrose and 8 parts water. These solutions should have SG's of 1.0400, 1.0611, and 1.0830 respectively.

This link explains how to calculate your wort correction factor.

Edit: Or, you could build your own "My refractometer reading to wort SG" calculator by taking both refract and hydrometer readings on lots of different worts, and then using a spreadsheet to determine a correlation equation.

Brew on

I was saying you want to use wort to determine your wort correction factor. No need for table sugar solution for any of this unless that’s what you’ll be fermenting. It doesn’t technically matter if 15 Brix is actually 15 brix. That’s what the wort correction factor corrects for. It’s like the first sentence to the webpage you linked (same page i first linked) says, “When taking a refractometer measurement of wort, the Brix reading is not necessarily accurate.” The refractometer is meant for grape juice or sucrose solution. Way different than beer wort.


You first want to zero it in with room temp water (first thing you should do prior to using it each time). This is just like any other lab instrument... calibrate it with contolled samples that are closest in range to what you plan to measure, bio 101.

 

[doug293cz]

I was saying you want to use wort to determine your wort correction factor. No need for table sugar solution for any of this unless that’s what you’ll be fermenting. It doesn’t technically matter if 15 Brix is actually 15 brix. That’s what the wort correction factor corrects for. It’s like the first sentence to the webpage you linked (same page i first linked) says, “When taking a refractometer measurement of wort, the Brix reading is not necessarily accurate.” The refractometer is meant for grape juice or sucrose solution. Way different than beer wort.


You first want to zero it in with room temp water (first thing you should do prior to using it each time). This is just like any other lab instrument... calibrate it with contolled samples that are closest in range to what you plan to measure, bio 101.

Your previous post used the word "calibration", and as BeardedBrews pointed out, that's different than correlation. I agree that to find a correlation factor between a particular instrument and SG, you don't actually have to calibrate the Brix scale.

But rather than using wort made from DME, I believe it is better to use wort from your normal brewing process to correlate between your refract and your hydrometer.

Brew on

 

[doug293cz]

Brix is the % of dissolved sugar in solution. Since if you dissolve 10 grams of sugar in about 100ml of water you should have a 10% solution, so to be closer, you use a volumetric flask of 100ml. This flask will have an etched line in the long neck that indicates where 100ml is (at the bottom of the meniscus) in that particular flask. Sugar added to water adds volume. We have to take that into account when we chapitalize, as there is extra volume (gallons of juice) from the added lbs of sugar. I measured out 10g of sugar in 100ml of water at home just now, and at 60 deg my hydrometer floats at the 10 Brix mark. It's not exact, as I said, because I don't have a volumetric flask at home. I have several at my lab in the winery, though. This link shows that if you have 10 Brix, you have 103.98 grams/L of sugar 1L = 1000 ml link: https://vinoenology.com/calculators/fermentation/

Your link has two conflicting definitions of the Brix scale. The first is that Brix is weight percent sucrose

"Brix (°Bx) is defined as the percentage of sugar by weight in a solution."​

And the second is that Brix is weight per volume

"Brix (°Bx) is a graduated scale, used on a hydrometer, which indicates the weight of sugar per volume of solution"​

I have been going by the Wikipedia provided definition(https://en.wikipedia.org/wiki/Brix.)

"Degrees Brix (symbol °Bx) is the sugar content of an aqueous solution. One degree Brix is 1 gram of sucrose in 100 grams of solution"​

I have been looking on line for something from a standards body that is more definitive than secondary sources, but am not having much luck (most standards bodies want to get paid for their publications.)

Brew on

 

[BIAB-Tim]

My new Brew Tapper Refractomenter with ATC With dual scale matches my Hydrometer to the tee ! Brix matches the SG preboil post boil with my Hydrometer 4 different times wort cooled to 70F ! I will see how much different it is after Fermentation is over I know it will not be spot with Hydrometer due to the alcohol, but it as made it easier to get my SG OG pre & post during brew day !

 

[portguy]

Your link has two conflicting definitions of the Brix scale. The first is that Brix is weight percent sucrose

"Brix (°Bx) is defined as the percentage of sugar by weight in a solution."​

And the second is that Brix is weight per volume

"Brix (°Bx) is a graduated scale, used on a hydrometer, which indicates the weight of sugar per volume of solution"​

I have been going by the Wikipedia provided definition(https://en.wikipedia.org/wiki/Brix.)

"Degrees Brix (symbol °Bx) is the sugar content of an aqueous solution. One degree Brix is 1 gram of sucrose in 100 grams of solution"​

I have been looking on line for something from a standards body that is more definitive than secondary sources, but am not having much luck (most standards bodies want to get paid for their publications.)

Brew on

Details

Making a Standard % Brix (Sucrose) Solution

To make a Brix Solution, follow the procedure below:

Place container (such as a glass vial or dropper bottle that has a cover) on an analytical balance.
Tare the balance.
Weigh out X grams of high purity sucrose (CAS #: 57-50-1) directly into a beaker
Add distilled or deionized water to the beaker so the total weight of the solution is 100g.
Note: Solutions above 65% may need to be vigorously stirred or shaken and heated in a water bath to roughly 40°C (104°F). Remove solution when sucrose has dissolved and allow to cool before use.

https://hannainst.com/50-brix-standard-solution-10-ml-hi4020-11.html

 

[Miraculix]

The SGs listed on the refractometer aren’t accurate. Brix/sg relationship is not linear. The brix/sg conversion listed on those refractometer is based on grapes / wine, not grains/beer. Just use brewersfriend calculators to convert brix to s.g.. (https://www.brewersfriend.com/refractometer-calculator/). You can further increase accuracy by determining your wort correction factor (https://www.brewersfriend.com/how-to-determine-your-refractometers-wort-correction-factor/).

Once you figure out your wort correction factor your refractometer will be very similar to your hydrometer... frequently within a few percent. For awhile I used both a hydrometer and refractometer for every measurement. I found them so close, I ditched by hydrometer. E.g. I’d get an sg of 1.052 and an abv of 5.2% with my refractometer and 1.051 /5.1% with my hydrometer. They were almost always 1-3 points from each other over 20+ brews.

Now I only out of hydrometer if I get a reading on refractometer that doesn’t make sense/ far from what I was expecting. I really just want to know 1) am I close to predicted og and 2) am I close to predicted fg? I don’t obsess over a few gravity points.

Note: even if you get one with ATC, you’re still going to want to let it get close to room temp (temp you calibrated it to). Often times I’ll give the dropper 30 secs to cool down (time it takes me to walk inside to get refractometer). Then placing a small drop on the room temp refractometer brings temp down the rest of the way.

If you would be a merchant, you would have instantly sold me one. Going to get myself one the next days! Thanks for the info!

 

[Nebraskan]

I have been looking on line for something from a standards body that is more definitive than secondary sources, but am not having much luck (most standards bodies want to get paid for their publications.)

Brew on

Here is the thing. I asked at work another winemaker about Brix. 100 ml of water weighs 100 grams. So you and I are both right. 10 grams in 100 mls is 10% ref: http://mathcentral.uregina.ca/QQ/database/QQ.09.06/s/shian1.html

 

[hawkbox]

That is the beautiful thing about metric.

 

[doug293cz]

Here is the thing. I asked at work another winemaker about Brix. 100 ml of water weighs 100 grams. So you and I are both right. 10 grams in 100 mls is 10% ref: http://mathcentral.uregina.ca/QQ/database/QQ.09.06/s/shian1.html

Not quite. 10 grams of sugar + 100 ml of water equals 110 grams of solution. 10 g / 110 g = 0.091 or 9.1 wt% = 9.1°Bx. However, if you add water to 10 grams of sucrose to make 100 ml of solution, you will use significantly less than 100 ml of water, so the error will be much small than 0.9°Bx. I'll figure out what the exact error is, and post back here.

And, to be really pedantic, 100 ml of water only weighs 100 grams at 4°C. At 20°C (68°F) 100 ml of water weighs only 99.82 grams. Not a big error, but if you're calibrating, you want to be as precise as possible.

Brew on

 

[portguy]

Not quite. 10 grams of sugar + 100 ml of water equals 110 grams of solution. 10 g / 110 g = 0.091 or 9.1 wt% = 9.1°Bx. However, if you add water to 10 grams of sucrose to make 100 ml of solution, you will use significantly less than 100 ml of water, so the error will be much small than 0.9°Bx. I'll figure out what the exact error is, and post back here.

And, to be really pedantic, 100 ml of water only weighs 100 grams at 4°C. At 20°C (68°F) 100 ml of water weighs only 99.82 grams. Not a big error, but if you're calibrating, you want to be as precise as possible.

Brew on

Even when using wheight/volume there's an obvious catch: if adding 100 ml of water to 10 grams of sugar, the end solution will be 115,9 ml , as sugar has a 1,59 g/cm³ density.

It's good info when making priming solution in a target volume that is easily divided.

 

[doug293cz]

Even when using wheight/volume there's an obvious catch: if adding 100 ml of water to 10 grams of sugar, the end solution will be 115,9 ml , as sugar as a 1,59 g/cm³ density.

If you assume ideal solution theory (solution volume = component 1 volume + component 2 volume), then 10 grams of sucrose at 1.59 g/ml is 10 g / 1.59 g/ml = 6.29 ml. So, with 100 ml of water the total volume would be 106.29 ml. I don't believe sucrose in water follows ideal solution theory, but at around 10°Bx the error is quite small.

Brew on

 

[portguy]

If you assume ideal solution theory (solution volume = component 1 volume + component 2 volume), then 10 grams of sucrose at 1.59 g/ml is 10 g / 1.59 g/ml = 6.29 ml. So, with 100 ml of water the total volume would be 106.29 ml. I don't believe sucrose in water follows ideal solution theory, but at around 10°Bx the error is quite small.

Brew on

Yes. Of course you are right. That is how i calculate my target volume exactly when priming with a syringe.

 

[Nebraskan]

At the winery today I took in my refractometer and zeroed it with deionized water (from our special resin filter) I ran brix on 3 grape samples with a 24-16 Brix hydrometer and then tried the same juice on the refractometer. It was about 2 deg Brix low. What I did was use one of the 3 samples that was 23.2 Brix on the refractometer and using the small screwdriver, adjusted the refractometer to read 23.2. I then tested the other 2 juice samples that were close to this Brix reading and now it was spot on. I am not sure how accurate it would be when reading down around 13 deg Brix.

BTW my Dad lived in Renton WA when he was alive and retired from Boeing. He managed to get me a job out there at Plant II back in 1977. Beautiful country when you get outside of the city *like in the Cascades*.. kind of OT but

 

[doug293cz]

At the winery today I took in my refractometer and zeroed it with deionized water (from our special resin filter) I ran brix on 3 grape samples with a 24-16 Brix hydrometer and then tried the same juice on the refractometer. It was about 2 deg Brix low. What I did was use one of the 3 samples that was 23.2 Brix on the refractometer and using the small screwdriver, adjusted the refractometer to read 23.2. I then tested the other 2 juice samples that were close to this Brix reading and now it was spot on. I am not sure how accurate it would be when reading down around 13 deg Brix.

BTW my Dad lived in Renton WA when he was alive and retired from Boeing. He managed to get me a job out there at Plant II back in 1977. Beautiful country when you get outside of the city *like in the Cascades*.. kind of OT but

Not surprising that a juice sample might not read the same as a sucrose sample, just like a wort sample doesn't read the the same as sucrose. A hydrometer always reads SG, no matter what is in solution.

Back to the OT. My dad also worked for Boeing for a time (on the 747), but I never did. I actually left the Puget Sound region for work in late 1977, but moved back in 2013 to retire. It's still beautiful, but you have to go a little farther to get away from the population density.

Brew on

 

[Nebraskan]

This link might be of use in this thread. It talks about wort correction, and making up a 20 Brix/ 1.083 S.G. solution using DME and water. https://www.brewersfriend.com/how-to-determine-your-refractometers-wort-correction-factor/

Just for clarification on the above post, I was not adding 10 grams to an already 100 ml of water (which would be 110g ) but it was added as "Part Of" the 100 ml. Sugar dissolves and will take up space, so to be more accurate, 10 grams was added to "some" water in a 100ml volumetric flask, allowed to dissolve, and then the volume was brought up to the line representing 100 mls in the volumetric flask. I think it comes closer that way to an actual 10% solution, but not an exact ... but close.