Reading gravity out of the bottle

[ChiBrew]

I just cracked open a bottle from my 2nd batch and it tastes great. However, I took a gravity reading and it's coming out to be 1/2 the alcohol content. (OG=1.045, Gravity out of the bottle=1.026). I'm pretty sure I hit my numbers before I bottled. Does it change that much after 2 weeks in the bottle? Pardon my ignorance, but I couldn't find any information on this specific situation.

 

[Yooper]

I just cracked open a bottle from my 2nd batch and it tastes great. However, I took a gravity reading and it's coming out to be 1/2 the alcohol content. (OG=1.045, Gravity out of the bottle=1.026). I'm pretty sure I hit my numbers before I bottled. Does it change that much after 2 weeks in the bottle? Pardon my ignorance, but I couldn't find any information on this specific situation.

Gravity doesn't go up in the bottle- but in order to get a true reading, you need to decarbonate the sample. The co2 bubbles will hold the hydrometer higher, giving a false reading.

Whatever the SG was at bottling is what it is now.

 

[Hello]

No. What was the temp of the liquid you measured? I think you need to convert for that at the very least. Also, it is cabornated, right? That'll mess it up. Beer doesn't lose alcohol content over time, that I know of. In fact, I know it doesn't increase because I started a dumb thread on it not too long ago and was quickly reminded how much of a moron I can be.

 

[ChiBrew]

No. What was the temp of the liquid you measured? I think you need to convert for that at the very least. Also, it is cabornated, right? That'll mess it up. Beer doesn't lose alcohol content over time, that I know of. In fact, I know it doesn't increase because I started a dumb thread on it not too long ago and was quickly reminded how much of a moron I can be.

Thanks for the info. I actually used a refractometer. Does the carbonation still make a difference?

 

[hophop]

Refractometers are inaccurate on fermented beer. You have to use a refractometer with an online conversion calculator once fermentation begins.

 

[Yooper]

Refractometers are inaccurate on fermented beer. You have to use a refractometer with an online conversion calculator once fermentation begins.

Right. That explains the very high reading- the refractometer doesn't work when alcohol is in the mix. The hydrometer, however, does!

 

[Johnnyhitch1]

I just cracked open a bottle from my 2nd batch and it tastes great. However, I took a gravity reading and it's coming out to be 1/2 the alcohol content. (OG=1.045, Gravity out of the bottle=1.026). I'm pretty sure I hit my numbers before I bottled. Does it change that much after 2 weeks in the bottle? Pardon my ignorance, but I couldn't find any information on this specific situation.

OG 1.045 = ~11.2 Brix
Gravity from bottle 1.026 = ~6.5 Brix

Corrected for post fermentation alcohol content your FG should have been ~1.014