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For instance, this one. The refractometer measures refraction if light for sucrose solution. When alcohol is present, refractometer of light changes and requires use of a calculator.
A little science experiment
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https://www.brewersfriend.com/beer-priming-calculator/
this calculator is how i came up with the amount of priming sugar to use
this calculator is how i came up with the amount of priming sugar to use
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so if I'm understanding the calc you linked. for me to properly use it I would need a good og which I most likely don't have due to the oddball hydrometers I was using at the start. according to the refractometer the brix is around 9.8 if I'm reading it correctly and the sg side reads 1.038 using the calc it states 1.039 on the og side.
not nessasarily. do you still your dinky hydros? or a gram scale and measuring cup?
if you get a current SG reading, you can compare it to the refrac and reverse figure out how much alcohol is there, and what the og was...or pretty close anyway...
if you get a current SG reading, you can compare it to the refrac and reverse figure out how much alcohol is there, and what the og was...or pretty close anyway...
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if i use what I started with then according to the calc I'll have a 5.42% abv but i'm betting more on the 4.8 side when finished with conditioning.
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i have a good hydro as well now that read close to 1.037 ish after spinning. the sample temp at immersion read 68.
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I've not ever personally verified this, but there is a calculator that will estimate your original specific gravity, OG, if you measure a DEGASSED (means get all bubble out by whisking, stirring, or pouring back and forth) ROOM TEMPERATURE sample of finished beer, using both hydrometer and refractometer. Measure SG of final beer sample (eg 1.0##) and brix/plato of final beer sample (eg 5.#) and use the calculator here.
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ill try this when i open a bottle to test in a week
Roughly speaking, a refractometer is meant to measure the sugar content in water. When used to measure that content in a water/alcohol mixture, the SG reading will be incorrect. Depending on your use of the refractometer and your desired precision, it’s possible to use the refractometer reading to approximate the actual SG. Online calculators can be helpful.
Refractometers respond to refractive index (how strongly something bends light passing through it at an angle.) It's possible to calibrate the concentration of lots of things in binary solutions with water against the refractive index of the solution, and then measure the concentration with a refractometer. Sugar concentration is the one we care about, and is what a Brix refractometer reads, but you can also buy refracts that measure salinity of salt water, and you could calibrate one to measure alcohol in a binary solution containing only ethanol and water.
The problem is beer contains more than ethanol and water (dextrins, proteins, etc.) Measuring beer (not wort) with a refractometer is analogous to trying to solve for two variables with one equation. Adding in the OG measurement to the final Brix measurement, gives us the second equation that we need when solving for two variables.
Mixing sugar with water increases the index of refraction, the more sugar the higher the index of refraction. Mixing ethanol with water also increases the index of refraction, and again the more ethanol the higher the index of refraction. In either case you can correlate the index of refraction to the concentration of solute. If you mix both sugar and ethanol with water, the index of refraction also increases, but there is no way to tell from the refractive index measurement how much of the increase was due to sugar, and how much was due to ethanol - unless you have some more information.
Brew on
Excellent in-depth explanation—thanks.Refractometers respond to refractive index (how strongly something bends light passing through it at an angle.) It's possible to calibrate the concentration of lots of things in binary solutions with water against the refractive index of the solution, and then measure the concentration with a refractometer. Sugar concentration is the one we care about, and is what a Brix refractometer reads, but you can also buy refracts that measure salinity of salt water, and you could calibrate one to measure alcohol in a binary solution containing only ethanol and water.
The problem is beer contains more than ethanol and water (dextrins, proteins, etc.) Measuring beer (not wort) with a refractometer is analogous to trying to solve for two variables with one equation. Adding in the OG measurement to the final Brix measurement, gives us the second equation that we need when solving for two variables.
Mixing sugar with water increases the index of refraction, the more sugar the higher the index of refraction. Mixing ethanol with water also increases the index of refraction, and again the more ethanol the higher the index of refraction. In either case you can correlate the index of refraction to the concentration of solute. If you mix both sugar and ethanol with water, the index of refraction also increases, but there is no way to tell from the refractive index measurement how much of the increase was due to sugar, and how much was due to ethanol - unless you have some more information.
Brew on
Not to stray too far off topic: what type of plane is in your profile pic?
Nice! Never flown a Vans of any variant, but I’ve heard great things. My only LSA experience is with an Evektor Sportstar. Not IFR equipped, unfortunately…Vans RV-12. Two seater, Light Sport Aircraft.
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1.037 seems really high for an FG.
Can you post a picture of the relevant portion of the hydrometer? We can confirm that something isn't being misread.
If you put the amounts of lme and the liquid volume into a recipe calculator does it give you a really high OG? Like over 1.100? That might be a reason why the fermentation stopped so high.
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Well, where to begin with the update on this? I've been dealing with several things on a personal level, so I have been poor at updating this. First according to my notes the 1.037 was the gravity reading was not the final gravity but a test done with a proper hydrometer after the confusion I was having with the oddball ones I started with. the FG at bottling was 1.005. I conditioned with dme as the primer at 1 cup water to 2.07oz DME according to the calculator Homebrew Priming Sugar Calculator for priming 2 gal of beer at 2.3 co2. The beer at the time of bottling was dark amber and mostly clear. I pulled a bottle and found that the beer did not carbonate well at all it reminded me of an old British style of pub beer that would be flat by the time the pint was poured.
As for the taste all in all it was okay malty with little to no hop flavoring slightly cidery with a very strong acidic taste at the end. While this in the eyes of many would be an "I told you so!" moment I found it to be a success in a few ways. 1. The taste was exactly what my troops described when talking to them about it. 2. When I had one of them over this weekend I gave them one to try and they expressed that it was better than they remember it being while being just as bad. This reaffirms to me what I expected to have been one of the issues dealt with in Iraq. Heat does in fact cause premature aging of liquid extracts. Making it taste much older than it is. It also confirms that I won't be buying the older kits that they are selling at the small hardware store here in town as they have been there for many years. I will be dumping this project in the next few days.
I do not feel that this was a waste of time but in fact, has only strengthened my dislike for pre-hopped extracts as well as teaching my partner and a few other friends the value of fresh kits as well as all grain or partial grain brewing.
As for the taste all in all it was okay malty with little to no hop flavoring slightly cidery with a very strong acidic taste at the end. While this in the eyes of many would be an "I told you so!" moment I found it to be a success in a few ways. 1. The taste was exactly what my troops described when talking to them about it. 2. When I had one of them over this weekend I gave them one to try and they expressed that it was better than they remember it being while being just as bad. This reaffirms to me what I expected to have been one of the issues dealt with in Iraq. Heat does in fact cause premature aging of liquid extracts. Making it taste much older than it is. It also confirms that I won't be buying the older kits that they are selling at the small hardware store here in town as they have been there for many years. I will be dumping this project in the next few days.
I do not feel that this was a waste of time but in fact, has only strengthened my dislike for pre-hopped extracts as well as teaching my partner and a few other friends the value of fresh kits as well as all grain or partial grain brewing.
I'm glad you got some value out of it. Figuring out the gravity measurement issues with the batch seems worthwhile, too.
If it tasted sour then it may have also gotten infected. It might be worthwhile to check your cleaning and sanitizing processes so that the next batch of something good isn't adversely affected.
BrewnWKopperKat
ʘ‿ʘ
Back in #7, you made a number of comments that made it clear (at least to me) that this wasn't a "let's brew with old 'extract' - because [faux] science!" idea.
Thanks for the followup!
moving on to the more general topic
LME stored improperly (and perhaps shipped hot) darkens excessively. That being said, techniques for evaluating the color of LME pre-boil have been in print since 2015 (and probably before that). In combination with a couple of other vendor articles "
I'm not (yet) convinced that all LME has this problem. How much of the problem is improper storage at the destination? During shipping? due to (re)packaging? How would one begin to measure this?
Why look into this further? Because 'style specific' extracts exist and appear to be an interesting additional ingredient for brewing.
However, one can get color as expected with 'extract':
This was the 1st bottle from a DME based recipe I brewed about six weeks ago. It wasn't chilled (so no chill haze).
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