Spike Brewing 12.5 Conical Fermenter Giveaway - Enter Now!

Home Brew Forums > Home Brewing Beer > All Grain & Partial Mash Brewing > Too high of gravity, with low volume: AG batch

Reply
 
LinkBack Thread Tools
Old 09-14-2009, 10:10 PM   #1
rshosted
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Posts: 123
Liked 2 Times on 2 Posts
Likes Given: 3

Default Too high of gravity, with low volume: AG batch

I've been searching for this problem on here without luck. I've ran into this problem many times, but not sure how to deal with it best. So I'm looking for others who may know.

I do 5 or 10 gal batches, all grain, with fly sparge. I've done probably about 15 batches so far.

While brewing, I test my runoff with a refractometer. I know going below 2-3 brix (balling) will get a bitter astringent taste. So I usually stop around 2 brix.

So I did a recipe that called for 70% efficiency, and should have ended runoff with 13.g gallons pre boil. Then after boil should have been 11 gallons at 1.041.

Now I ended runoff with 11 gallons at 14.4 brix (1.059 brix). Added 1.5 gallons of water. After boil ended at 11 gallons with sg 1.048

So I ended with too high of gravity, with too low of volume...

So I figure there are a few things I can do:
Sparge slower (already at 60+ minutes)
Sparge faster
Add water at the end (this time I did add 1.5 gallons to get the gravity and volume to match where I wanted, but I worry about diluting flavor of the beer).

So, how much water can one add after runoff without diluting flavor (preboil). Is this common? Or how can I get more runoff without ruining my efficiency?

I hope this makes sense, because I think I'm confusing myself here..

Thanks in advance,
Ryan

__________________

Last edited by rshosted; 09-14-2009 at 10:13 PM.
rshosted is offline
 
Reply With Quote Quick reply to this message
Old 09-14-2009, 10:13 PM   #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: 60,717
Liked 4367 Times on 3175 Posts
Likes Given: 850

Default

Quote:
Originally Posted by rshosted View Post
I've been searching for this problem on here without luck. I've ran into this problem many times, but not sure how to deal with it best. So I'm looking for others who may know.

I do 5 or 10 gal batches, all grain, with fly sparge. I've done probably about 15 batches so far.

While brewing, I test my runoff with a refractometer. I know going below 2-3 brix (balling) will get a bitter astringent taste. So I usually stop around 2 brix.

So I did a recipe that called for 70% efficiency, and should have ended runoff with 13.g gallons pre boil. Then after boil should have been 11 gallons at 1.041.

Now I ended with 11.5 gallons at 14.4 brix (1.059 brix). After boil ended at 11 gallons with sg 1.04

So I ended with too high of gravity, with too low of volume...

So I figure there are a few things I can do:
Sparge slower (already at 60+ minutes)
Sparge faster
Add water at the end (this time I did add 1.5 gallons to get the gravity and volume to match where I wanted, but I worry about diluting flavor of the beer).

I don't quite understand. You ended up at OG 1.040 with 11 gallons, but were shooting for 1.041? That's not a difference. I'm sure that I am not understanding your question.
__________________
Broken Leg Brewery
Giving beer a leg to stand on since 2006
Yooper is offline
 
Reply With Quote Quick reply to this message
Old 09-14-2009, 10:15 PM   #3
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: 60,717
Liked 4367 Times on 3175 Posts
Likes Given: 850

Default

Ah, you edited it. Ok, I see the issue now!

The easiest fix would just be to adjust your recipe for the efficiency you're getting.

What I like to do is to make my recipe based on my efficiency. I also make my boil volume a fixed amount, so that I don't sparge until I have low SG runnings. I just sparge to get my boil volume. What I mean is this- I want to boil 6.25 gallons for my 5.25 gallon batch. So, after my mash, I sparge until I have 6.25 gallons in the kettle and just stop. I usually batch sparge, but sometimes will fly sparge up to my boil volume.

So, say I mash in with 3.5 gallons. I draw off 2.5 gallons from my first runnings. That means I need 3.75 gallons of sparge water. That will give me my boil volume.

That's the easiest way to make sure you hit your volumes. If you also plug in your efficiency for the recipe, then you'll have dependable results with each brew.

__________________
Broken Leg Brewery
Giving beer a leg to stand on since 2006
Yooper is offline
 
Reply With Quote Quick reply to this message
Old 09-14-2009, 11:43 PM   #4
ajf
Senior Member
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
ajf's Avatar
Recipes 
 
Join Date: Oct 2005
Location: Long Island
Posts: 4,643
Liked 99 Times on 93 Posts
Likes Given: 39

Default

Quote:
Originally Posted by rshosted View Post
Now I ended runoff with 11 gallons at 14.4 brix (1.059 brix). Added 1.5 gallons of water. After boil ended at 11 gallons with sg 1.048
I think that this is part of your problem.
If you start with 11g at 1.059, add top off water and evaporate water during the boil so you end up with 11g, you must end up with the same gravity that you started with as the volume has not changed. One of your brix readings must have been incorrect, and I would guess that it was the pre-boil reading. I would also guess that this reading was off because the wort had not been adequately stirred before taking the sample.

-a.
__________________

There are only 10 types of people in this world. Those that understand binary, and those that don't.

ajf is offline
 
Reply With Quote Quick reply to this message
Old 09-15-2009, 03:32 AM   #5
rshosted
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Posts: 123
Liked 2 Times on 2 Posts
Likes Given: 3

Default

ajf, you are correct and I apologize, I did get off incorrect Brix numbers because I was recalling from memory. Although, what I should have done is just make an example with correct numbers.

lets say I'm getting 11 gallons of runoff stopping at 2 brix ending runoff, with a batch of 1.050 (total 11 gal prior to boil).

The recipe should be at 1.035 at 13 gallons, to evaporate off 2 gallons at 1.040 SG finished batch.

Now if I boil off 2 gallons from my finish, that leaves me with 9 gallons (yeah I'm not good at math here), and a much higher SG, Say 1.060 (guessing numbers here). But if I add 2 gallons of water, at least I finish close, say 11 gal at 1.050, instead of 9 at 1.060.

Hopefully this makes sense. I just don't see how to end the runnings at the correct volume, and correct SG. It seems that I get less volume and correct (or at least closer) S.G.

All that aside, I have adjusted my promash to set me up to a closer efficiency rating for future batches.

__________________
rshosted is offline
 
Reply With Quote Quick reply to this message
Old 09-17-2009, 10:57 PM   #6
rshosted
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Posts: 123
Liked 2 Times on 2 Posts
Likes Given: 3

Default

bump? Hopefully this made sense....

__________________
rshosted is offline
 
Reply With Quote Quick reply to this message
Old 09-23-2009, 05:26 PM   #7
rshosted
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Posts: 123
Liked 2 Times on 2 Posts
Likes Given: 3

Default

okay, so I tried something to get my answer; I emailed a local brewmaster (whom I did not know). He was very nice and offered some ideas. (actually I asked for one of my favorite brew recipes and he gave me a really good start to get it done too!)

He suggested that I was using too much grain for my recipe, and that I was sparging too quick. He said I should be getting 1 gallon per 15 minutes. I'm a bit skeptical since that would put a 10 gallon batch (yeilding 13 gallons of runnoff) at 3 hr 15 minutes.

right now I'm running about 60-80 minutes for this batch.... Maybe I'll have to try and dramatically slow it down for my next batch (although, I thought it was already really slow).
-R

__________________
rshosted is offline
 
Reply With Quote Quick reply to this message
Old 09-23-2009, 07:16 PM   #8
rshosted
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Posts: 123
Liked 2 Times on 2 Posts
Likes Given: 3

Default

Somehow I lost this post, but I'll repeat it... although not as well as the first.

I contacted a local brewery and asked the brewmaster there what he thought of this problem. He said I was over-shooting my grainbill and sparging too quickly. He said I should be sparging at 1 gallon every 15 minutes.

This seemed a bit high to me, since for a 10 gallon batch, I usually run off about 13 to account for evaporation, kettle loss, trub loss, etc. So far, I've been taking about 60-80 minutes to sparge a 10 gallon batch. I guess I'll have to slow it down, but by his accounts I'll be looking at 3hr 15 minutes.... seems a touch long to me...???

Anyone ever actually taken 15 minute per gallon in a sparge?

__________________
rshosted is offline
 
Reply With Quote Quick reply to this message
Old 09-24-2009, 01:12 AM   #9
ajf
Senior Member
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
ajf's Avatar
Recipes 
 
Join Date: Oct 2005
Location: Long Island
Posts: 4,643
Liked 99 Times on 93 Posts
Likes Given: 39

Default

I'm sorry that I didn't get back to post #5, but I've been away for a few days.
I think that your first problem is that your pre-boil gravity reading is inaccurate.
In your first post, you said that your pre-boil reading was 14.4 brix (1.059 SG). According to my calculations, 14.4 brix translates to a SG of 1.056. You then said that you added 1.5g water and boiled back to your original volume and ended up with a gravity of 1.048. As I said previously, if you add a volume of water, and boil that volume of water off, you must end up with the same gravity that you started with, yet you have more than 18% discrepancy.
You are either getting bad gravity readings, or your volume measurements are inaccurate, or both.
Before taking a pre-boil gravity reading, you must stir the wort really well, and then take the sample from the main body of the wort. Don't take a sample from the spigot at the bottom of the kettle especially if you have a false bottom in the kettle, as any wort trapped under the false bottom will have a higher gravity than the main body of the wort. If you do have a false bottom that has to be in place before taking the pre-boil gravity sample, you can stir the wort to mix it well, then drain off a gallon or so from below the false bottom, and add it back to the top and stir again before taking the reading. This will eliminate any stratification, and give you an accurate reading.
Another possible reason for getting a low gravity reading after the boil is leaving wort in the kettle when transferring to the fermenter. If you leave 10% of the wort in the kettle because of hop absorption, trub, and dead space, you will lose 10% efficiency, and will end up with a lower OG than if you transferred everything. Also, if you take the OG with the hydrometer, and your hydrometer and/or refractometer is not calibrated, you could introduce errors from incorrectly calibrated measuring equipment.
As for the Brewmasters comments, it seems that you ended up with a higher gravity than you wanted, so if your gravity and volume measurements were correct, you are getting more than 70% efficiency and need to reduce the grainbill to compensate.
As for sparging at 1g every 15 minutes, I used to get close to that when using a 5g MLT for beers with an OG of about 1.075, but I can sparge at about twice that rate with minimal loss in efficiency with a 10g MLT.

Hope this helps.

-a.

__________________

There are only 10 types of people in this world. Those that understand binary, and those that don't.

ajf is offline
 
Reply With Quote Quick reply to this message
Old 09-25-2009, 04:28 AM   #10
rshosted
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2008
Posts: 123
Liked 2 Times on 2 Posts
Likes Given: 3

Default

AJF,

I was using, in post #5 illustrative numbers, to demonstrate the point of what is happening. When I say, "let's say", I'm assuming hypothetical numbers to determine the problem.

I am getting better than 70% efficiency. I'm not accounting for loss because I'm taking a measurement in the boil kettle.

You said you got an og of 1.075, but that doesn't tell me if it was under or over, as I didn't know what you were expecting.

I guess I'll shoot for 15 minutes like the brewmaster told me and hope for the best.

__________________
rshosted 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
Hybrid Batch Sparging for High Gravity Brews FlyGuy All Grain & Partial Mash Brewing 8 05-04-2011 03:08 PM
First Batch: Final Gravity Reading Too High Blueberryspies Beginners Beer Brewing Forum 1 07-28-2009 01:53 AM
Batch Sparging with High Gravity Beers? cs2to4 All Grain & Partial Mash Brewing 5 06-30-2009 03:00 PM
Batch sparge - high gravity beers phidelt844 All Grain & Partial Mash Brewing 5 01-06-2009 03:33 PM
Batch sparging high gravity beers FlyGuy All Grain & Partial Mash Brewing 13 05-30-2007 07:12 PM