Get your HBT Growlers, Shirts and Membership before the Rush!


Home Brew Forums > Wine, Mead, Cider, Sake & Soda > Cider Forum > How to calculate FG?
Reply
 
LinkBack Thread Tools
Old 10-09-2008, 02:23 AM   #1
Fireguy
Feedback Score: 0 reviews
Recipes 
 
Join Date: Sep 2008
Location: Midwest
Posts: 23
Default How to calculate FG?

I know I have had a few questions recently, but I have been wondering how to calculate my gravities? If my OG is 1.071, what can I expect for my FG? and how or what equation do u use to get it? I hope im posting this in the right forum....since its on cider i thought why not? thanks folks

__________________
Fireguy is offline
 
Reply With Quote Quick reply to this message
Old 10-09-2008, 02:27 AM   #2
Yooper
Ale's What Cures You!
HBT_ADMIN.png
Feedback Score: 0 reviews
 
Yooper's Avatar
Recipes 
 
Join Date: Jun 2006
Location: Upper Michigan
Posts: 62,907
Liked 4952 Times on 3588 Posts
Likes Given: 1002

Default

In order to guestimate the FG, you have to know the probable or likely attenuation of the yeast, or the ABV threshold of the yeast. For example, montrachet will probably go to 14% in a healthy fermentation. Or, in a beer, you can plan on 75% attenuation for Nottingham yeast.

Most wine yeasts will take anything under 1.100 totally dry, depending on ingredients.

__________________
Broken Leg Brewery
Giving beer a leg to stand on since 2006

Find me on facebook: Lorena Evans
But I'm pretty boring so don't expect much!
https://www.facebook.com/lorena.t.evans
Yooper is offline
 
Reply With Quote Quick reply to this message
Old 10-09-2008, 01:53 PM   #3
Tusch
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2007
Location: Spring Valley, Ohio
Posts: 1,381
Liked 10 Times on 8 Posts

Default

To give numbers to Yooper post, with almost any wine yeast, you can expect anything from 1.100 or lower to go all the way to between 1.000-.990 generally

__________________
Meads: Hababero and Sarrano Capiscumel, Show Mead possibly getting split and flavored, and 12 gallons of Bochet Deliciousness
Ciders:3 Ciders with differing additives TBD, Strawberry/Apple Cider
Wine: Black Cherry Vanilla Port
Tusch is offline
 
Reply With Quote Quick reply to this message
Old 10-09-2008, 06:43 PM   #4
Pogo
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2008
Posts: 344
Liked 1 Times on 1 Posts

Default

Fireguy -

If the Original Gravity (OG) of your batch is 1.071, and the Final Gravity (FG) turns out to be, say, 0.998.

To estimate the Alcohol By Volume (ABV), simply subtract the FG from the OG, and multiply the result by 131.

(OG - FG) X 131 = % ABV

1.071 - 0.998 = 0.073 X 131 = 9.563 % ABV

Pogo

__________________
Pogo is offline
 
Reply With Quote Quick reply to this message
Old 10-09-2008, 11:08 PM   #5
lapaglia
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2008
Location: Denver, Colorado
Posts: 511
Liked 4 Times on 4 Posts

Default

Quote:
Originally Posted by Pogo View Post
Fireguy -

If the Original Gravity (OG) of your batch is 1.071, and the Final Gravity (FG) turns out to be, say, 0.998.

To estimate the Alcohol By Volume (ABV), simply subtract the FG from the OG, and multiply the result by 131.

(OG - FG) X 131 = % ABV

1.071 - 0.998 = 0.073 X 131 = 9.563 % ABV

Pogo
Slight OT.
I always used this for final ABV.
OG-FG/7.36*1000 = %ABV
1.071 - 0.998 = 0.073 / 7.31 = 0.00998 * 1000 = 9.98 ABV.

Forget the fact that its a little more math. I have seen both formulas use. Is there a way to tell which is better or closer to the actual?

In addition the "Joy of Homebrewing" (AKA the BIBLE as some people say) says the equation is og-fg x 105, as brewmonkey says og-fg x 131.

Fermcalc says OG 1.071 - FG 0.998 = 9.9 %ABV
__________________
Primary: 3 gallon cider S-04
Secondary: Valentine Apfelwein Clone 1 Gal
Bottled: Halloween Apfelwein Clone 1 Gal
On Deck: 90 Shilling Clone

lapaglia is offline
 
Reply With Quote Quick reply to this message
Old 10-10-2008, 12:50 AM   #6
Fireguy
Feedback Score: 0 reviews
Recipes 
 
Join Date: Sep 2008
Location: Midwest
Posts: 23
Default

Thanks folks!!! that is exactly what I need to know. Guess Ill just have to wait till it stops fermenting to know for sure.

__________________
Fireguy is offline
 
Reply With Quote Quick reply to this message
Old 10-10-2008, 07:47 AM   #7
Pogo
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2008
Posts: 344
Liked 1 Times on 1 Posts

Default

lapaglia -

Thanks for opening my eyes a little bit.

I've been totally unaware that there was more than one way to compute ABV.

Maybe someone with access to a refractometer will test their SG readings and verify which method is superior.

Thanks for the class!

Pogo

__________________
Pogo is offline
 
Reply With Quote Quick reply to this message
Old 10-10-2008, 12:30 PM   #8
lapaglia
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2008
Location: Denver, Colorado
Posts: 511
Liked 4 Times on 4 Posts

Default

Quote:
Originally Posted by Pogo View Post
lapaglia -

Thanks for opening my eyes a little bit.

I've been totally unaware that there was more than one way to compute ABV.

Maybe someone with access to a refractometer will test their SG readings and verify which method is superior.

Thanks for the class!

Pogo
No problem, now the real thing is to figure out which it the most accurate for what we are doing. Its possible all the methods are as accurate as the next one as its all approximate readings. Hopefully someone smarter than I am has the answer.
__________________
Primary: 3 gallon cider S-04
Secondary: Valentine Apfelwein Clone 1 Gal
Bottled: Halloween Apfelwein Clone 1 Gal
On Deck: 90 Shilling Clone
lapaglia is offline
 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
can someone calculate my efficiency for me? TacoGuthrie Beginners Beer Brewing Forum 2 08-24-2009 07:38 AM
Can someone calculate this... dirtymike1 Recipes/Ingredients 3 08-25-2008 09:13 PM
How do you calculate Efficiency ? karbinator All Grain & Partial Mash Brewing 4 03-29-2008 05:47 PM
how to calculate ABV?? kfgolfer Beginners Beer Brewing Forum 5 12-26-2006 12:04 AM
How to calculate IBU? ratm4484 Beginners Beer Brewing Forum 2 12-10-2006 10:24 PM



Newest Threads

LATEST SPONSOR DEALS