Very low FG (1.002)

[bbbblaine]

I brewed the following recipe: http://www.brewtoad.com/recipes/california-cream

I started with an OG of 1.050 on 7/3

I fermented at 60-65F

On 7/17, I lowered the temp to 35F to cold crash it

On 7/18, I took a sample out of the spigot at the bottom of the bucket.
The gravity read 1.002, which seems extremely low to me.

There was quite a bit of sediment in the sample that I took, so could that be throwing off the gravity reading somehow? Or is there another reason that the FG is so low?

 

[knuckleheadbrewing]

Get a clean sample with as little trub/yeast/sediment as possible and measure again....However, it's not impossible that you fermented down that low.. My wife makes wine and I have measured the wine for her and came out at ~.995 (alc. is lighter then water, you can fall below 1.000 when there is more alc. then water).

SO get that clean seample and test again..also make sure your wort sample is 60* that is what a hydrometer is calibrated to measure correctly at. If your reading is correct you'll be at a 6% ABV beer!

 

[brycelarson]

Couple of things - if you're using a hydrometer then temp matters - they're calibrated at 68 degrees. Let the sample come to room temp to get an accurate measurement.

And yeah,you want a clean sample - chunks can throw it off.

 

[bbbblaine]

I don't use a hydrometer anymore. I use a refractometer that claims to give accurate readings regardless of temperature.

I will take another sample in a few hours and see how that goes

 

[pm5k00]

I don't use a hydrometer anymore. I use a refractometer that claims to give accurate readings regardless of temperature.

I will take another sample in a few hours and see how that goes

Refracometers need a calculation/ conversion when reading FG. I have never used one, but have seen countless threads about it here, they are very good for OG readings, but spotty for FG. It would be best to use a hydrometer for FG readings.

 

[Yooper]

I don't use a hydrometer anymore. I use a refractometer that claims to give accurate readings regardless of temperature.

I will take another sample in a few hours and see how that goes

A refractometer can't be accurate when alcohol is in the solution, as it throws off the way the light refracts. Take a reading with a hydrometer. There are "correction" tables on the internet for refractometers but I've never had one reading, even corrected, be accurate.

 

[bbbblaine]

To correct the FG, I use the refractometer calculator at this website http://onebeer.net/refractometer.shtml

When I take a (hopefully cleaner) sample, I'll take a reading with the refractometer and my old hydrometer to see if there is a difference.

 

[greenbirds]

Highly recommend using a calibrated hydrometer vs a refractometer and correction calculator for FG.

Also, suspended chunks (hops, trub, yeast) do not affect the density of the sample and thus will not mess up your hydrometer sample, unless of course there is so much that the base of your hydrometer is resting in it. With a refrac, yes, probably best to get a clean sample.

 

[bbbblaine]

Update: I measured with a hydrometer and got a 1.011 reading which is awesome. Note to self: use hydrometer for determining FG. It looks like that thing will still be useful to me afterall!

 

[matt2778]

Couple of things - if you're using a hydrometer then temp matters - they're calibrated at 68 degrees. Let the sample come to room temp to get an accurate measurement.

And yeah,you want a clean sample - chunks can throw it off.

Mine are both calibrated at 60. At 68 they're a point and half off.

 

[brycelarson]

Mine are both calibrated at 60. At 68 they're a point and half off.

mine is 20C. Most people round that off to 70 - I was trying to be precise.

best advice - check the manual.