Electric Brewing Supply 30A BCS Giveaway!


Home Brew Forums > Home Brewing Beer > All Grain & Partial Mash Brewing > Efficiency Question(s)
Reply
 
LinkBack Thread Tools
Old 01-07-2013, 01:57 PM   #1
Guidry
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2009
Location: Denham Springs, La
Posts: 629
Liked 29 Times on 27 Posts
Likes Given: 4

Default Efficiency Question(s)

1. Is efficiency based on pre-boil gravity, or post boil? Seems to me it should be pre-boil as you are measuring your extraction of sugars from the grain, but maybe I am wrong.

2. Yesterday, I brewed a batch of Janet's Brown. I hit my pre-boil graivty right on the expected, 1.055 with 7.5 gals in the kettle. Problem is that my (post-boil) OG measured came in at 1.062 vs the expected 1.068. To add to my frustration, I ended up with only 5.25 gals as opposed to the 5.5 gals I was expecting. When I realized I was short on volume, I expected that my OG might come in higher, but that wasn't the case. Anyone have any ideas on this?

__________________
Guidry is offline
 
Reply With Quote Quick reply to this message
Old 01-07-2013, 02:12 PM   #2
Odin_Brews
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2011
Location: golden, CO
Posts: 265
Liked 19 Times on 18 Posts
Likes Given: 10

Default

Mash efficiency is based on your pre-boil OG, brewhouse efficiency takes into account your losses to evap/kettle/whirlpool etc and uses the final OG and final volume when it goes into the fermenter. I seem to recall an article on beersmith's website that goes into this in more detail. I think you could also take into account loss in the fermenter as well and use your bottling volume to get your final brewhouse efficiency.

As to your situation on Janet's brown, that seems pretty odd and I have no helpful explanation. I typically hit my preboil OG and water volumes but end up low on the software predicted OG postboil (particularly with beers over 1.060), I just know it's coming and compensate as the calculators relating boil off to increase in OG don't seem to fit my system

__________________
Odin_Brews is offline
 
Reply With Quote Quick reply to this message
Old 01-07-2013, 02:16 PM   #3
TyTanium
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2011
Posts: 3,949
Liked 549 Times on 387 Posts
Likes Given: 418

Default

Don't forget expansion - you're usually measuring pre-boil volumes hot and post-boil cold. The difference is 1-2 quarts.

Here's a common correction formula:
=Measured Gallons /(1+(Measured Temp-68)*0.000264)

__________________
TyTanium 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
Efficiency question rcp197 General Beer Discussion 3 10-04-2012 12:46 AM
Efficiency question Deeznuttz All Grain & Partial Mash Brewing 11 05-02-2012 05:26 PM
Efficiency Question ryanpaulnorris All Grain & Partial Mash Brewing 2 09-20-2010 11:44 AM
efficiency question Kronin General Techniques 6 07-20-2009 02:53 PM
Efficiency question OhioMurb All Grain & Partial Mash Brewing 5 05-25-2009 12:08 AM