specific gravity vs alcohol %
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- napsternova
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specific gravity vs alcohol %
I'm just wondering what the difference is between testing for alcohol content and specific gravity? Am I wrong in thinking that if my batch tests appropriate for alcohol content that it's ready to bottle?
Re: specific gravity vs alcohol %
Wellllll.... yes and no. If, based on your measured OG and FG readings, think you are at the abv you expected, you may well be done. But sometimes the yeasties like to party a little longer than the estimate. The best way, IMHO, is to take readings over a few days. If they are stable (i.e., you get the same reading each day), you're likely done.
Swenocha is a vast bastard of brewing knowledge - Wings_Fan_In_KC
Fermenting:
nada... zip...
Drinking:
nada... zip... maybe an N/A beer here and there...
Fermenting:
nada... zip...
Drinking:
nada... zip... maybe an N/A beer here and there...
- HerbMeowing
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Re: specific gravity vs alcohol %
Testing for alcohol content won't tell you if fermentation is over.
A recipe's ABV is an estimate only.
As for sampling daily; such a waste.
If you must; then draw a sample.
Sample again three days later.
Stable? It's 'GO' for packaging!
More better - let it ride three weeks ... then package.
Better to go long than risk bottle bombs.
A recipe's ABV is an estimate only.
As for sampling daily; such a waste.
If you must; then draw a sample.
Sample again three days later.
Stable? It's 'GO' for packaging!
More better - let it ride three weeks ... then package.
Better to go long than risk bottle bombs.
Homebrew will get you through times of no money
Better than money will get you through times of no homebrew
- apologies to the Fabulous Furry Freak Brothers
Better than money will get you through times of no homebrew
- apologies to the Fabulous Furry Freak Brothers
Re: specific gravity vs alcohol %
I suppose I should have been more clear, as I didn't really mean to take readings daily (yes, that would be a waste). I'm saying the exact same thing you are... If you take a couple readings spread over a few days, and you get the same reading each day, you are likely done.
Swenocha is a vast bastard of brewing knowledge - Wings_Fan_In_KC
Fermenting:
nada... zip...
Drinking:
nada... zip... maybe an N/A beer here and there...
Fermenting:
nada... zip...
Drinking:
nada... zip... maybe an N/A beer here and there...
- Dawg LB Steve
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Re: specific gravity vs alcohol %
At the 2 week mark I pull my sample, check gravity then wad up a paper towel,foam plug or even a sanitzed piece of foil loosely covering the top to keep wild stuff out, the CO2 will push it out a bit if it is still fermenting but you are only using one sample tube. At the end I pour it off slowly ( so I don't get any of the layer of trub ) into a pint mason jar and put in the fridge to get a taste of what's to come once it is carbed up.
MONTUCKY BREWING
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Re: specific gravity vs alcohol %
Becoming more familiar with the attenuation rate of different yeast strains, or how completely they're expected to ferment wort sugars into alcohol and Co2 may be the answer to your question. Under the best conditions for example White Labs WLP810 - San Francisco Lager Yeast™ will only attenuate 65-70% of your original gravity reading. I use Screwy Calc to do the math for me but a quick method of calculating AA% is to divide your original gravity by 4.napsternova wrote:I'm just wondering what the difference is between testing for alcohol content and specific gravity? Am I wrong in thinking that if my batch tests appropriate for alcohol content that it's ready to bottle?
OG = 1.050 (Shorten it to 50)
50 / 4 = 12.5 for a final gravity of 1.0125
But there's a catch, the apparent attenuation (AA%) to take 1.050 down to 1.025 works out to be 73%, which is higher than WLP810's 70% maximum range. Another thing to remember is that once the final gravity readings are stable for two days the yeast still needs several more days to cleanup the fermented beer, without changing the final gravity. I hope this helps.
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Re: specific gravity vs alcohol %
The short answer is don't brew for ABV by trying to take some existing recipe and jack it up. That doesn't make better beer.
Instead, find recipes/styles of beer that are intended to be at a higher ABV to begin with and try those. That will be easier once you get beyond the HME and brew with extract and your own hops.
A slightly longer answer is that if you must, then more malt extract (assuming you are extract brewer) is normally better then sugar until you are brewing a style that sugar is more appropriate in.
In brew demon terms those would be the "pale horse", "red horse", "white horse", and "black horse" cans of extract. Just find the one that has similar attributes to the beer you are making (color, flavor) and throw in a can of it.
Those will make better beer then the "enhancer" most of the time.
Instead, find recipes/styles of beer that are intended to be at a higher ABV to begin with and try those. That will be easier once you get beyond the HME and brew with extract and your own hops.
A slightly longer answer is that if you must, then more malt extract (assuming you are extract brewer) is normally better then sugar until you are brewing a style that sugar is more appropriate in.
In brew demon terms those would be the "pale horse", "red horse", "white horse", and "black horse" cans of extract. Just find the one that has similar attributes to the beer you are making (color, flavor) and throw in a can of it.
Those will make better beer then the "enhancer" most of the time.
Re: specific gravity vs alcohol %
Hi Edwin, welcome to the Borg!
Mashani is a very smart brewer, it is wise to listen to him. I agree that it is better to brew according to established recipes and kit instructions to gain experience. I was tempted to experiment by modifying kits when I first started too. The results were not very good. Then I studied brewing, and practiced. I still make mistakes, but I also make some really good beer. You will too.
Mashani is a very smart brewer, it is wise to listen to him. I agree that it is better to brew according to established recipes and kit instructions to gain experience. I was tempted to experiment by modifying kits when I first started too. The results were not very good. Then I studied brewing, and practiced. I still make mistakes, but I also make some really good beer. You will too.
Making beer and stew for the Zombie Apocalypse.
Never mind, there it is.
Never mind, there it is.
- Whamolagan
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Re: specific gravity vs alcohol %
Ok there is a little different trains of thought here. You can get a Specific gravity of the same reading 3 days in a row, and fermentation may be done converting sugars. That is a start, there are other things that are happening after conversion from sugars to alcohol and co2. Without going deep into all of the details, there are other compounds that need to be cleared out like sulfur and diactyls. If bottled too early, these can come through in the final taste. Most will settle out after time. One of the best ways is to taste test before bottling or kegging. I like to go by clarity and taste. Just my 2 cents that is worth beach front property in Arizona
Re: specific gravity vs alcohol %
+1mashani wrote:The short answer is don't brew for ABV by trying to take some existing recipe and jack it up. That doesn't make better beer.
Instead, find recipes/styles of beer that are intended to be at a higher ABV to begin with and try those. That will be easier once you get beyond the HME and brew with extract and your own hops.
A slightly longer answer is that if you must, then more malt extract (assuming you are extract brewer) is normally better then sugar until you are brewing a style that sugar is more appropriate in.
In brew demon terms those would be the "pale horse", "red horse", "white horse", and "black horse" cans of extract. Just find the one that has similar attributes to the beer you are making (color, flavor) and throw in a can of it.
Those will make better beer then the "enhancer" most of the time.
The worst beer I ever made was one agate I was chasing abv. It ended up around 9%, but s was almost undrinkable. I also brewed a beer that came in over 10% and was delicious. The difference is that the second beer was high abv because it fit the recipe and the first was because I was just going for high abv.
- Dawg LB Steve
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Re: specific gravity vs alcohol %
^^^^^^^^^^^^^^^^ YEP THIS^^^^^^^^^^^^^^^^^^^mashani wrote:The short answer is don't brew for ABV by trying to take some existing recipe and jack it up. That doesn't make better beer.
Instead, find recipes/styles of beer that are intended to be at a higher ABV to begin with and try those. That will be easier once you get beyond the HME and brew with extract and your own hops.
A slightly longer answer is that if you must, then more malt extract (assuming you are extract brewer) is normally better then sugar until you are brewing a style that sugar is more appropriate in.
In brew demon terms those would be the "pale horse", "red horse", "white horse", and "black horse" cans of extract. Just find the one that has similar attributes to the beer you are making (color, flavor) and throw in a can of it.
Those will make better beer then the "enhancer" most of the time.
MONTUCKY BREWING
Actively brewing since December 2013Re: specific gravity vs alcohol %
thanks guys im using it according to the recipe ..lol
Re: specific gravity vs alcohol %
Good idea, Ed. Keep us posted. There are recipes and kits for thousands of beers, this is great ride.
Making beer and stew for the Zombie Apocalypse.
Never mind, there it is.
Never mind, there it is.
Re: specific gravity vs alcohol %
And once you start making your own, there's no limit to the number of possibilities (just don't go hog wild adding ingredients right off the bat; learn what different things bring to the table first).John Sand wrote:Good idea, Ed. Keep us posted. There are recipes and kits for thousands of beers, this is great ride.