Specific Gravity and ABV

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CarolusMag

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I guess you would say I am somewhat new to brewing beer. I started with 3 batches or so with a 'Mr. Beer' many years ago and found out that was not enough. I moved up to 5 gallon batches and I just bottled my 4th batch last week. I have been very happy with each batch I have made. I follow the recipe instructions very carefully ( specialty grains and malt extract...not yet an all grain brewer). I sanitize religiously. I leave it in the fermenter for 2 weeks. Bottle condition for 2 or more weeks. The results have always been great. I love it. The people I pass out my brew to love it. It looks good, tastes good, and it gives me the warm fuzzies.
However I have to admit I have NEVER checked my OG or my final SG. I have not know what the exact ABV is on my beers. So my question is this....
What am I missing? I admit there is likely some minor something missing as far as perfection or consistency but I brew new flavors pretty much each time. ALl this talk about specific gravity and final gravity and ABV. Does everyone do it? I know what it is and what it is used for, but am I the only one that thinks it is unnecessary?
 

catalanotte

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Not sure I would go as far as necessary for an extract brewer, but very helpful to monitor the progress of the beer and make it repeatable. Also has some safety implications like ensuring a stable FG for bottling so you don't risk bottle bombs. Should you go to all-grain you will find that monitoring gravities is an essential piece of information to help develop your process, repeat the outcome of your best beers, and troubleshoot issues.
 

hotbeer

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It depends on how much you wish to get into controlling what your end result is. And knowing the SG of your wort or beer at various steps in the process can help with troubleshooting issues. And of course knowing the OG and the SG can let you know what your ABV is and having the same ABV for a particular beer does affect how it's taste is perceived. So consistency for getting the same taste with the same recipe each time.

But if you are getting the results you want there isn't any real reason to take a SG reading other than adding that to your notes for future purposes if ever needed.

For basic and beginning brewing using a hydrometer seems to have new brewers overly worried and overly concerned. I consider hydrometers and SG readings a thing for advance brewing and not needed for first time brewers till they get use to doing all the procedures of basic brewing.

Once they achieve a level that you seem to indicate you have, then they can consider if they want a hydrometer. Otherwise a accurate thermometer is all that is needed.
 

ncbrewer

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Extract has a published ppg (points per pound per gallon) - it is totally predictable. Steeped grains aren't exact, but they lend so little to the OG that any error is minor. So I haven't taken OG readings for many years with extract batches. But FG is important if you bottle. Checking gravity twice, three days apart, will tell you if fermentation is actually finished. Sometimes it doesn't follow the expected schedule. If you bottle before it's finished, it will finish in the bottle and give you overcarbonation. It could even cause bottle bombs. I use a narrow range bottling hydrometer for FG to make sure it's ok to safely bottle.
 
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CarolusMag

CarolusMag

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Not sure I would go as far as necessary for an extract brewer, but very helpful to monitor the progress of the beer and make it repeatable. Also has some safety implications like ensuring a stable FG for bottling so you don't risk bottle bombs. Should you go to all-grain you will find that monitoring gravities is an essential piece of information to help develop your process, repeat the outcome of your best beers, and troubleshoot issues.
Thanks for taking the time to answer. Prosit!
 

AlexKay

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I’ve beat this drum before, but if you’re measuring gravity to monitor fermentation progress, to diagnose a stuck fermentation, to decide when it’s time to bottle, or to check that your process is repeatable … a refractometer works every bit as well as a hydrometer. And it’s much harder to break one.
 

skeeterman

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Extract has a published ppg (points per pound per gallon) - it is totally predictable. Steeped grains aren't exact, but they lend so little to the OG that any error is minor. So I haven't taken OG readings for many years with extract batches. But FG is important if you bottle. Checking gravity twice, three days apart, will tell you if fermentation is actually finished. Sometimes it doesn't follow the expected schedule. If you bottle before it's finished, it will finish in the bottle and give you overcarbonation. It could even cause bottle bombs. I use a narrow range bottling hydrometer for FG to make sure it's ok to safely bottle.
While I do check SG and FG, I also take a sample with my wine thief. I then tilt the thief over to about 45 degrees. If there are tiny bubbles rising up the tube, I am not quite done yet.
 

catalanotte

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While I do check SG and FG, I also take a sample with my wine thief. I then tilt the thief over to about 45 degrees. If there are tiny bubbles rising up the tube, I am not quite done yet.
An ale fermented at room temperature has about 1 vol of dissolved CO2 in solution. It will come out of solution easily and is not an indicator of continued fermentation. Ignore the bubbles and trust a stable FG for 3 days.
 

catalanotte

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… a refractometer works every bit as well as a hydrometer. And it’s much harder to break one.
Yes. I have a few broken hydros to back this up. A refractometer with a calculator is all I use unless something looks wonky. Then I’ll do a comparison at the time I keg to verify both OG and FG.
 

skeeterman

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An ale fermented at room temperature has about 1 vol of dissolved CO2 in solution. It will come out of solution easily and is not an indicator of continued fermentation. Ignore the bubbles and trust a stable FG for 3 days.
Thanks. Live and learn.
 

YeastFeast

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When I first started, I considered measuring gravity one of the most important things you could do (other than maybe sanitation). My second batch ever I did a oatmeal stout and got a stuck fermentation. Who knows what I did wrong but I couldn't get it to ferment out. I would have been beyond pissed if I had done 50 bottles of this and they were all garbage. Better to know for sure.
 

hout17

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Yes. I have a few broken hydros to back this up. A refractometer with a calculator is all I use unless something looks wonky. Then I’ll do a comparison at the time I keg to verify both OG and FG.
We just need to emphasize (to newer brewers) once fermentation has started and gravity is dropping that you can't read the refractometer directly as there are conversions needed to properly calculate gravity as you alluded to regarding a calculator.
 
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CarolusMag

CarolusMag

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When I first started, I considered measuring gravity one of the most important things you could do (other than maybe sanitation). My second batch ever I did a oatmeal stout and got a stuck fermentation. Who knows what I did wrong but I couldn't get it to ferment out. I would have been beyond pissed if I had done 50 bottles of this and they were all garbage. Better to know for sure.
Most of the responses seem to confirm the importance of readings....especially in all grain brewing which now makes sense to me. Thanks for the response. How to you 'unstick' that fermentation you refer to?
 

YeastFeast

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Most of the responses seem to confirm the importance of readings....especially in all grain brewing which now makes sense to me. Thanks for the response. How to you 'unstick' that fermentation you refer to?
I never did figure that one out. It was literally my 2nd batch ever. I took a ABV reading and it was like 20 points from being finished (according to the ABV estimate on the brew sheet) and just stopped. I even bought another package of dry yeast and pitched it thinking I could get it going again but it never fermented out. After all this it was super oxidized too and tasted like cardboard. I ended up dumping it....which is why I said I would have been really pissed had I gone through all the trouble of bottling it and THEN dumping them all...UGH. You are right in the fact that if everything goes well, no need to know the exact ABV. But if it doesn't....
In the future, there are other reasons you may want to take gravity readings during your process (e.g. mash efficiency, etc)
 
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