Ss Brewing Technologies Giveaway!

Home Brew Forums > Home Brewing Beer > General Beer Discussion > Pre Boil vs. OG
Reply
 
LinkBack Thread Tools
Old 10-15-2012, 02:06 AM   #1
Toy4Rick
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2011
Location: Oceanside, Ca
Posts: 374
Liked 13 Times on 12 Posts
Likes Given: 1

Default Pre Boil vs. OG

Hey gang,

Is there a direct corelation between Pre boil gravity and OG? Meaning, a 1 hour boil in same equipment, similiar boil rate... will produce "x" increase in gravity?

I seem to float between .05 and .09 over the past 6 brews. Today seemed to be of the lowest and I am not sure why

Thanks in advance
Toy4Rick

__________________
Toy4Rick is offline
 
Reply With Quote Quick reply to this message
Old 10-15-2012, 02:12 AM   #2
pcollins
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2010
Location: Cambridge, ON
Posts: 549
Liked 27 Times on 25 Posts
Likes Given: 37

Default

Usually, yes.

Atmospheric pressure, humidity, temperature, etc., all have a bearing on your boil off rate. As you brew more you'll figure out your average but there will be lows and highs. It's not fixed.

__________________
pcollins is offline
 
Reply With Quote Quick reply to this message
Old 10-15-2012, 12:35 PM   #3
Xpertskir
Feedback Score: 6 reviews
Recipes 
 
Join Date: May 2012
Location: Morgantown, Wv
Posts: 2,030
Liked 388 Times on 252 Posts
Likes Given: 21

Default

Yes but it's not linear in fact I think it's parabolic.

Gravity is the measure of the density of sugar in water so

A pre boil gravity of 1.040 is not going to increase as much over the same boil off rate as a 1.050 pre boil gravity.

__________________
Xpertskir 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
Making my own Boil kettle: Formula for pre-boil vs post boil anyone? brewjedi General Beer Discussion 4 08-02-2012 04:14 AM
Full Boil Extract Boil with question on batch volumes tjashing Extract Brewing 11 05-02-2012 03:19 PM
First full boil - questions regarding strength of boil, hop utilization, hot break heyjaffy Beginners Beer Brewing Forum 3 04-14-2011 01:56 AM
What adjustment should I make to hops for full boil vs. partial boil? DaveAllen Beginners Beer Brewing Forum 18 03-15-2010 02:46 AM
Question about water amount in full boil or partial boil neldred Beginners Beer Brewing Forum 6 10-17-2009 03:50 AM