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Old 02-08-2011, 10:14 AM   #1
DoctorDuvel
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Default Gravity reading after bottling is in another league compared to FG at bottling...

So I brewed up a Saison late last summer. The FG (or so I thought) was 1.007 at bottling, but I just opened a bottle earlier tonight and took a gravity reading (an excuse to use my refractometer) and was astounded to find the reading over 1.020. I used a hydrometer for the FG at bottling, and I took multiple readings prior to bottling, noting the gradual progression down to 1.007. So, assuming I didn't screw up the readings, does anyone have an idea about this? ...or did I screw up the readings?

I will say that I thought my Saison always has tasted different, maybe "heavier" than I wanted to be.


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Old 02-08-2011, 11:47 AM   #2
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did you do "alcohol correction" for the refractometer?


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Old 02-08-2011, 11:51 AM   #3
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You have to take into account the presence of alcohol, and co2 in your sample. I've really never heard of anyone having the need to take a post bottling reading...that could be why.

Where would the presence of unfermentables that would lower the gravity be coming from? How would something "un-ferment?"

In other words...Operator error.......
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Old 02-08-2011, 11:56 AM   #4
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The presence of alcohol would tend to lower the gravity reading. Post-bottling sampling would be higher due to the CO2. If you want an accurate way to measure, take your sample and shake/stir to get all the CO2 out of solution. Then measure and you should have the same (or very close) SG as to when the beer was bottled.
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Old 02-08-2011, 10:19 PM   #5
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Ooooooh! Ok, these things did (very) briefly cross my mind. I guess I thought the refractometer was a little more magical than it really is. I'm just relieved my pre-bottling readings were the right ones.

Revvy, with over 26,000 posts and all the experience you have, I will take my having done something you have never heard of as a compliment and an original contribution to the HBT archives.

Ace_Club, I'll try that next time...Thanks guys!


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