Final Gravity Seems High

[beerman75]

My last two brew's final gravity seem high. I did an all grain porter using dry yeast and SG was 1.055, FG was 1.030, calculated ABV of 3.5%

Latest brew is a Scottish Ale using liquid Wyeast. SG 1.061, FG 1.032, calculated ABV 3.8%.

Are those reasonable numbers? Or am I maybe not doing something right?

Larry

 

[raysmithtx]

Are you using a refractometer to get the FG reading? If so, you need to adjust the reading to take the alcohol into consideration.

 

[beerman75]

Are you using a refractometer to get the FG reading? If so, you need to adjust the reading to take the alcohol into consideration.

Yes I am. How does one adjust the reading?

 

[beerman75]

After some reading, let's see if I understand.
I can measure the OG with the refractometer.
I measure Brix at the end of fermentation and use an online calculator to convert to SG and get ABV.

 

[raysmithtx]

Yep. That's the way I do it. I brewed several batches and tested the adjusted refractometer reading with a hydrometer reading. The readings were pretty much identical and as a result I have only used a refractometer for my last 60 batches or so. I do calibrate my refractometer with distilled water before each brew.

This is the best site I have found for accurately adjusting the refractometer for the presence of alcohol.

http://seanterrill.com/2012/01/06/refractometer-calculator/