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Old 10-19-2012, 09:01 PM   #1
W0rthog
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Yet another newb question.
I goofed when pitching my yeast into an Oktoberfest, because I didn't make a starter. With 1 smack pack, there was lag, but i believe the beer reached the proper final gravity.
My question is this; if a beer reaches final gravity, does this mean it finished fermenting?
My concern is my beer may be too sweet due to low yeast count. I'll know in 2 months when it's done lager'ing.
Thanks in advance

 
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Old 10-19-2012, 09:05 PM   #2
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"Final gravity" is ONLY determined by when the gravity reading is stable over a few samples taken days apart. Don't ever get it from a number you saw somewhere. Every beer does it's own thing.
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Old 10-19-2012, 09:43 PM   #3
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In short, yes Final Gravity means final gravity or complete fermentation. As tre9er stated, every beer will finish differently as there are a lot of factors involved in a beer reaching its final gravity so just because a recipe tells you it should be 1.xxxx doesn't mean your beer will be there when done. Some may be higher, some lower but if you take a couple samples over a few days and they remain the same then the beer is done.
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Old 10-19-2012, 09:53 PM   #4
Matt3989
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The low yeast count won't affect the final sweetness of your beer, that's determined by the amount unfermentable sugars you have in you're recipe. if your final gravity is supposed to be 1.018, it will be a much sweeter beer than say 1.005. Remember, gravity readings are just a measure of how much sugar is resolved in a liquid.

That being said, an under pitch (low initial yeast count) can give you some off flavors because it initially puts extra stress on the yeast. However, the yeast do do a fairly good job cleaning up after themselves, they'll remove some of the off flavors given time.

If you tell us the OG we'll be able to tell you how badly (if at all) you underpitched. But i wouldn't worry about it, I've never known anyone to do a starter on their first brew.... I've done a few without starters and they've turned out delicious.

 
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Old 10-19-2012, 10:11 PM   #5
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Are you doing all grain? I found that mashing at the wrong temp made me miss my final gravities in the beginning. Too hot and you'll be sweet, too low and you'll be too thin.

 
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Old 10-19-2012, 10:21 PM   #6
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Quote:
Originally Posted by tre9er View Post
"Final gravity" is ONLY determined by when the gravity reading is stable over a few samples taken days apart. Don't ever get it from a number you saw somewhere. Every beer does it's own thing.
How true.
I routinely finish a few points lower that the predicted FG.

 
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Old 10-19-2012, 11:25 PM   #7
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I'll be honest - I just let mine sit in the primary for 3-4 weeks. I take my gravity reading then. After a month it should be done and I trust the brew to bottles. No bottle bombs after doing it this way for 3 years.
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Old 10-19-2012, 11:30 PM   #8
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Don't confuse done fermenting with done and ready to bottle. Yes you can bottle when it is done fermenting but if you give it a little extra time the yeast will clean up some of the off flavors and you will have a better tasting beer.

 
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Old 10-19-2012, 11:50 PM   #9
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Quote:
Originally Posted by Matt3989
The low yeast count won't affect the final sweetness of your beer, that's determined by the amount unfermentable sugars you have in you're recipe. if your final gravity is supposed to be 1.018, it will be a much sweeter beer than say 1.005. Remember, gravity readings are just a measure of how much sugar is resolved in a liquid.

That being said, an under pitch (low initial yeast count) can give you some off flavors because it initially puts extra stress on the yeast. However, the yeast do do a fairly good job cleaning up after themselves, they'll remove some of the off flavors given time.

If you tell us the OG we'll be able to tell you how badly (if at all) you underpitched. But i wouldn't worry about it, I've never known anyone to do a starter on their first brew.... I've done a few without starters and they've turned out delicious.
Excellent answer
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Originally Posted by davekippen View Post
Open log Fermenting and gas-can secondary?? I am planning my next brew right now!!

 
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Old 10-20-2012, 12:07 AM   #10
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Quote:
Originally Posted by manoaction
Are you doing all grain? I found that mashing at the wrong temp made me miss my final gravities in the beginning. Too hot and you'll be sweet, too low and you'll be too thin.
I'm doing an extract kit. Thanks for sharing.

 
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