Question about estimating ABV

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Neone
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Question about estimating ABV

Post by Neone »

So - I don't have an alcometer. I have a hydrometer.

I have a beer wash that I know is 6%ABV.

If I do a stripping run, and reduce the volume in half - can I accurately say that the ABV will be 12% ?

(and can I do this 2 more times and get a 48%ABV / 92 proof spirit?)
junkyard dawg
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Post by junkyard dawg »

No, depending on the still, your low wines should be from 40 to about 65%. That is a very rough estimate...

Most of the water will be left in the boiler, most of the etoh will be in the product. (low wines) So cutting the volume in half won't double the concentration. Use some simple tests, try burning a bit in a spoon. generally it won't burn at less than 50% abv. Try shaking some and 'read the bead' watch the bubbles and compare to some store bought of a known proof... The bubbles are big and dissapear fast at high proof, smaller and stay longer at lower proof. With practice, that is pretty accurate... Of course, taste a little and feel it... how fast does it evaporate off you hands... You can get a good idea with no alcometer.
Neone
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Post by Neone »

Ah. That's what I was afraid of. The math was too simple.

So, say that I'm starting with 10L of 6% beer.

Running my reflux column without packing, so, in essence as a pot still, I should be able to pull approx 1L - 1.4 L of ~40% - 60% ABV in the first run?
stoker
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Post by stoker »

you could measure the density of your spirit (or dilluted with a known quantity of distilled water) with a hydrometer.
and look for a list of densities of ethanol-water mixtures. each density equals a certain contentration.
-I have too much blood in my alcohol system-
Neone
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Post by Neone »

Hmm - a link to more detail on this or a bit more explanation would be very helpful. Sounds promising though.
stoker
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Post by stoker »

the difference between an alcoholmeter and a hydrometer is the scale and the range. a hydrometer (mostly more then 1kl/l) has an other range than an alcoholmeter (less then 1kg/l) and a hydrometer has a metric scale in kg/l and an alcoholmeter in % (alchol-water)

take a known volume of spirit, call it 'D' in liters. First you dillute your sprit untill it is measureable by the hydrometer, write down the amount of water you've added, call this 'L' in liters. measure the density of the dilluted spirit and call it 'C' in kg/l.

then is C*(D+L)/D the original concentration of spirit (aproximatly) in kg/liters.

now you need a conversionlist to get the kg/l into % or ° or abv
maybe someone knows where you can find one.

hope it's correct, it's late
-I have too much blood in my alcohol system-
junkyard dawg
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Post by junkyard dawg »

I sort of follow stoker, but I'm no mathmagician.... :oops:

You could always check a known product with your hydrometer and compare readings... might take some dilutions and simple math, but It might get close...

I probably wouldn't sweat it too much... wait till the alcometer arrives, and just run that still a few times. If its a reflux, and you have everything else right, you can probably get near the 60% side. (mine does) Don't be surprised if its lower and less volume... that takes some practice to get consistent. After only a few runs, you should have a good ballpark idea of the proof coming off.
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Husker
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Re: Question about estimating ABV

Post by Husker »

Neone wrote:So - I don't have an alcometer. I have a hydrometer.

I have a beer wash that I know is 6%ABV.

If I do a stripping run, and reduce the volume in half - can I accurately say that the ABV will be 12% ?

(and can I do this 2 more times and get a 48%ABV / 92 proof spirit?)
Easiest way, is to not be so damn cheap, and spend $7 on an alcoholometer.

H.
Neone
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Post by Neone »

Easiest way, is to not be so damn cheap, and spend $7 on an alcoholometer.
Yeah - I did. It broke in the mail, so the replacement is on its way. In the meantime, thanks for the tough love.

The equation makes sense to me. I'll try figuring it out that way, and then cross-check it with the alcometer when it gets here intact. Thanks Stoker and JD!
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Husker
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Post by Husker »

Neone wrote:
Easiest way, is to not be so damn cheap, and spend $7 on an alcoholometer.
Yeah - I did. It broke in the mail, so the replacement is on its way. In the meantime, thanks for the tough love.

The equation makes sense to me. I'll try figuring it out that way, and then cross-check it with the alcometer when it gets here intact. Thanks Stoker and JD!
hehe, tough love can be fun :twisted: Sux that you got a broken one though. However, simply wait a few days before distilling, and the replacement will be here.

H.
MisterSteve124
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Post by MisterSteve124 »

if it burns with a flame then it's above 50%
Neone
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Post by Neone »

It doesn't, so - I guess it's not. it flames up when the match hits it, and then it's out. I'd guess it's in the mid 40's.

That's actually perfect because the plan is to smooth it out with some diluted honey water - and that gives me some leeway to bring it down to 40% while back-sweetening.
junkyard dawg
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Post by junkyard dawg »

You mentioned two distillations early in this thread...

I would encourage you to do several runs and collect low wines from a few batches. Then combine all those together and run once more. You will have much more much better product.

good luck...
Still_Crazy
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Post by Still_Crazy »

junkyard dawg wrote:You mentioned two distillations early in this thread...

I would encourage you to do several runs and collect low wines from a few batches. Then combine all those together and run once more. You will have much more much better product.

good luck...

A'men. Now that I've been playing with the D'WG and birdwatchers straight sugar wash, I'm running at least two fermentations at a time. I'll have less alcohol than using the turbo and 17lbs of sugar that I was used to, but it's easier and you get a way better product the next time or two around, depending on your unit.

Sorry to hear about the breakage of your instrument there.... that does suck! :cry:

Mine was $6-fitty in the store and I have checked it against a bottle of store-bought liquor... came out right at 40%. I have since looked at and considered one of the finer alcoholmeters that reads in a more specific scale either higher or lower but for general stuff you will dig the one you get.
~ After all these years, a drop in time helps soothe my mind ~
stoker
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Post by stoker »

I was thinking about a formula to get the density of the distillate into an abv. but I have no succes, can anyone help me?
-I have too much blood in my alcohol system-
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