alcohol content

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kabrew

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just bottled my first batch and everything seems to be going as instructed, but have a question on the alcohol content.

OG was 1.036 when siphoned into secondary and was only about 1.05 when i bottled. According to hydrometer, alcohol content is only about 1.5%. Is that really correct? please tell me that i didn't just make a batch of o'douls!!:(

thank you!!
 
Measure OG before you add the yeast, not when transferring. Your number is probably low because the yeast had already consumed some of the sugars. What was your recipe?

Also, a change of 0.031 should be closer to 4% alcohol.
 
No, the potential alcohol scale on the hydrometer is pretty much meaningless for beer.

(OG - FG) * 131 is a good approximation of alcohol by volume.

(1.036 - 1.005) * 131 = .031 * 131 = 4.06%
 
OG was 1.036 when you siphoned to secondary? And 1.05 on bottle..... You have some serious errors in your process I believe.

Did you check gravity of the cooled wort, BEFORE pitching the yeast? If so what was it.

When you say you siphoned to secondary at 1.036, fermentation wasn't complete.

Gravity was 1.05 at bottling. This means you increased gravity from racking to Secondary to bottling.

Case in point is, measurements weren't taken at the right time, nor do they sound correctly taken. However, it all comes with time. If tastes good, then drink it.
 
Oh, didn't catch that your 1.036 was measured when going into secondary... that's not going to be your OG... What's the recipe?
 
recipe: Wheat

1 can of hopped malt extract
1.5-2.0 lbs of unhopped malt extract
1 oz hops (2/3 added while wort was boiling, 1/3 added after heat was turned off)
1 package of top fermenting yeast
1 package of bru-vigor
3/4 cup of corn surgar (for priming)

I got the recipe and instructions (double stage brewing) from Defalcos in Houston and followed them pretty closely. I also have Palmers book and his instrcutions differ slightly, so wasn't really sure what to do there.

being a novice, i went with defalcos and am hoping for the best!

thanks for your help everyone...!
 
ok, so the real number to pay attention to is the change in gravity? Man, there's a lot i don't know about this yet, but i'm having a blast learning!
 
It's not meaningless. You simply need to take the difference between OG and FG values.

I meant specifically the Potential Alcohol By Volume scale on the hydrometer. Maybe "meaningless" was a strong word. Inconvenient and less accurate.
 
The formula I learn is a little different, but the results are the same. You drop the decimal in your gravity readings. Take the difference and divide by 7.46. So the math would be:

1036-1005= 31

31 / 7.46 = 4.16 % ABV
 
Yeah, pretty much the same.

The formula I posted, written another way would be:
(OG - FG) / .00763

Yours written another way would be:
(OG - FG) / .00746

Close enough, either way. :)

Beersmith calculates 1.036 to 1.005 as 4.03% ... not sure what formula it uses.
 
ok, so the real number to pay attention to is the change in gravity? Man, there's a lot i don't know about this yet, but i'm having a blast learning!

Exactly. It makes sense when you think about it:

If you have some dissolved sugars in water, the liquid is denser than just plain water. The more sugar, the denser it is, and so the higher the specific gravity. But that one number in itself doesn't tell you anything about alcohol content...who knows how much of those sugars will be converted to alcohol.

Then you turn your yeasties loose on the sugars, and they metabolize some portion (most, but not all) of the sugar and produce alcohol. Now you have very much less sugar in solution and very much more alcohol (which is less dense than water). But you need to know what specific gravity you started with to be able to tell how much of the sugars that you had in solution are now no longer there.
 
I meant specifically the Potential Alcohol By Volume scale on the hydrometer. Maybe "meaningless" was a strong word. Inconvenient and less accurate.

Right. Take the potential alcohol value prior to ferment and subtract the post ferment potential alcohol value.

My point is, the scale works, you've just got to use it just like you do the gravity one.
 
So, if my second reading is higher than my first...

I likely screwed up the first reading?

My second came in a 1.017 and I thought my first was at 1.015 but I must have screwed up somehow. Is there anyway for me to guesstimate the alcohol%?
 
So, if my second reading is higher than my first...

I likely screwed up the first reading?

My second came in a 1.017 and I thought my first was at 1.015 but I must have screwed up somehow. Is there anyway for me to guesstimate the alcohol%?

Well, if you brewed an extract brew, you could calculate your O.G. based on the recipe and then use your measured F.G. to figure it out. But once the beer is bottled, without those numbers the only way to know for sure would be to have it tested at a lab.
 
1.017 is a really, really low starting gravity. So yeah, that probably wasn't a good reading.

Was it an extract or all-grain batch? What were the ingredients and batch size?
 
This was the recipe:

http://brewersconnection.com/recipes/redcap.htm

Brewed the wort on 12/9. After boil, I put in a gallon of ice, unfortunately it dropped the temperature to below 50, so had to reheat before pitching the yeast.

Pitched and got that odd reading of 1.015 immediately following pitching (because I had forgotten - it being my first time I failed there)

Got a reading today when moving everything to the bottling bucket of the 1.017.
 
Right. Take the potential alcohol value prior to ferment and subtract the post ferment potential alcohol value.

My point is, the scale works, you've just got to use it just like you do the gravity one.

That is how I do it and I don't worry much about fractions of alcohol that much, ballpark is good for me. Is it really a big deal for most people? I can understand if you are trying to hit a constant, but I guess in brewing something I drink for enjoyment I don't really care. I guess I can understand it for people (many here) who name their brews and all and want it to be consistent. I still write down SG and FG (makes me feel like a scientist I guess) but in the end it all comes down to me using the potential alcohol scale to put an alcohol content on the beer.
 
If you put the amount of water and extract in that the recipe listed, your starting gravity was 1.047.

So if you ended up at 1.015, your alcohol by volume is 4.17%.

It's pretty common to get inconsistent starting gravity readings for extract batches. It's not easy to thoroughly mix the wort and top-off water. But as long as you used the amounts of extract and water that the recipe listed, it's just about impossible to miss the anticipated starting gravity.
 
Thank you very much for the help on that one! I really appreciate the community here helping me through my first brew.
 
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