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Old 03-04-2013, 01:58 AM   #1
SATXbrew
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Feb 2008
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My brother and I brewed a Barley Wine last night and we got horrible results with our mash and I was wondering if anyone had some insight as to how I can modify my process.

This has happened twice now with our big beers that we've tried. I've done many successful normal gravity beers, but for some reason my calculations haven't been working for these big beers.

Grains
20lbs 2-Row
1.5 Crystal 90L
1.5 Buscuit

Mashed for about 1hr 20 mins at 148 degrees. Mash ratio of 1.75gallons x 23 lbs = 10 gallons for mash volume. My tun only held about 9 gallons.. Mash out was supposed to be about 5.5 gallons, actual was about 6.

Sparged with 3 gallons. As Im writing this I realized I multiplied my est. loss wrong. I used my old notes and calculated .2 of loss x 12.5. Should have been x 23. I dont think this was the issue. Almost all came out so we had about 9 gallons in kettle. We were shooting for 7 so this was way over our estimate. Using this method, I am usually spot on with my measurements.

My gravity before boil was about 1054 which is crazy with that much grain. My brother also did a Wee Heavy with about the same amount of grain and ended up with about 1070 gravity. That is better but still seems low for that much grain.

What can we do to improve this? Mash with less water? If I do that, would I sparge with more water?

We had DME on hand so we were still able to obtain 1094 OG, but I would like to be hitting those kind of numbers with the grain alone. Next time we are going to just take a gravity reading right after the mash.

Thanks for the feedback!!

 
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Old 03-04-2013, 02:07 AM   #2
tyzippers
 
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I'm not quite following:
Quote:
My gravity before boil was about 1054 which is crazy with that much grain.
Quote:
Next time we are going to just take a gravity reading right after the mash.
Unless I am misunderstanding something, what is the difference? Preboil vs right after the mash are the same readings in my book.

Now, if you collected 9 gallons of 1.054 wort, boiled to 5 gallons, then you should have had somewhere around 1.097 going into the fermenter. So, help me understand your problem a little better because the way I worked it out, you shouldn't have had a problem...right?

 
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Old 03-04-2013, 02:14 AM   #3
mattd2
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Quote:
Originally Posted by SATXbrew View Post
...Sparged with 3 gallons. As Im writing this I realized I multiplied my est. loss wrong. I used my old notes and calculated .2 of loss x 12.5. Should have been x 23. I dont think this was the issue. Almost all came out so we had about 9 gallons in kettle. We were shooting for 7 so this was way over our estimate. Using this method, I am usually spot on with my measurements.
...
Also this has me wondering. Do you mean that during the sparge you put 3 gallons in and 3 gallons out? That makes sense since you should get no absorbtion loss from the sparge since the grain is already wet.

So to get the story straight:
23# grain
10 gallons strike water (1.75 qt/#)
3 gallons sparge

I assume 0.2 G/# absorbtion so first runnings should have been about 5.4G
Then add 3 gallons sparge = 8.4G
Then to get down to 5.5 gallons you would need to boil off about 3 gallons which would be about a 2 hour boil for myself. How long did you boil for?

For big beer advice I would say look at mashing a bit thinnner and doing 2 sparges.
Say roughly 1.25 qt/# = 7 gallons strike (2.5 gallons 1st runnings)
Get a total runnings of about 7.5 gallons = two 2.5 gallon sparges
Boil for two hours total (boil off 2 gallons) - Boil for 1 hour then start your hop additions.

 
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Old 03-04-2013, 03:15 AM   #4
SATXbrew
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Quote:
Originally Posted by tyzippers View Post
I'm not quite following:



Unless I am misunderstanding something, what is the difference? Preboil vs right after the mash are the same readings in my book.

Now, if you collected 9 gallons of 1.054 wort, boiled to 5 gallons, then you should have had somewhere around 1.097 going into the fermenter. So, help me understand your problem a little better because the way I worked it out, you shouldn't have had a problem...right?
I mean to take a gravity reading before sparging.

Your thinking that it would go up to 1097 from 1054 just from boiling off that volume and getting down to 5 gallons? I've never actually boiled off that much volume, but its my understanding you dont get that much gravity difference from boiling..

We ended up adding 4lbs DME and boiled for hour and half to get up to 1094.

 
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Old 03-04-2013, 03:24 AM   #5
SATXbrew
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Quote:
Originally Posted by mattd2 View Post
Also this has me wondering. Do you mean that during the sparge you put 3 gallons in and 3 gallons out? That makes sense since you should get no absorbtion loss from the sparge since the grain is already wet.

So to get the story straight:
23# grain
10 gallons strike water (1.75 qt/#)
3 gallons sparge

I assume 0.2 G/# absorbtion so first runnings should have been about 5.4G
Then add 3 gallons sparge = 8.4G
Then to get down to 5.5 gallons you would need to boil off about 3 gallons which would be about a 2 hour boil for myself. How long did you boil for?

For big beer advice I would say look at mashing a bit thinnner and doing 2 sparges.
Say roughly 1.25 qt/# = 7 gallons strike (2.5 gallons 1st runnings)
Get a total runnings of about 7.5 gallons = two 2.5 gallon sparges
Boil for two hours total (boil off 2 gallons) - Boil for 1 hour then start your hop additions.
I dont know exactly how much we ended up with for the final volume since we chilled the wort straight to the 6.5 gallon carboy. There was about a gallon head room in there.

Yeah.. we were thinking of dropping it down to around 1.25 qt next time too. Maybe even a little lower. Might give your 2 sparge idea a try.

 
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Old 03-04-2013, 03:35 AM   #6
tyzippers
 
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Quote:
Originally Posted by SATXbrew View Post
I mean to take a gravity reading before sparging.

Your thinking that it would go up to 1097 from 1054 just from boiling off that volume and getting down to 5 gallons? I've never actually boiled off that much volume, but its my understanding you dont get that much gravity difference from boiling..

We ended up adding 4lbs DME and boiled for hour and half to get up to 1094.
I used this calculator. I used the second calculator on the page and used the following values:
Wort Volume: 9 GAL
Current Gravity: 1.054
Desired Volume: 5 GAL

Boiling down to a volume absolutely does increase your SG readings. It's pure science and not even just my opinion. By removing water from your wort (steam from boiling), you are increasing the concentration of sugars in your wort. This is can actually be calculated. Now, to boil off 4 gallons, your boil will end up having to boil for longer than an hour. Based on your boiloff rates, you can calculate that as well.

I'm not sure how useful taking a SG reading is before the sparge. The most useful reading is preboil. That will tell you what adjustments you may or may not need to make in terms of boiloff before you start your hop additions or by actually adding more water, which is unusual.

Reason: Added link

 
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Old 03-04-2013, 07:15 PM   #7
patthebrewer
 
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Did you mill your own grain, or did the LHBS do it for you? First thing I would look at is your crush.
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Old 03-04-2013, 07:21 PM   #8
CTR08
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As explained, of course how much you boil off impacts the SG! There is a fixed amount of sugar in your wort- it you boil off more water, the SG will be higher. There is more sugar by volume and this will mean more abv after fermentation.

That's why to get an accurate SG reading, take it just before pitching yeast. Also, as mentioned, a pre-boil reading will just help you figure out how much to boil off.

 
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Old 03-05-2013, 12:36 AM   #9
SATXbrew
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Quote:
Originally Posted by tyzippers View Post
I used this calculator. I used the second calculator on the page and used the following values:
Wort Volume: 9 GAL
Current Gravity: 1.054
Desired Volume: 5 GAL

Boiling down to a volume absolutely does increase your SG readings. It's pure science and not even just my opinion. By removing water from your wort (steam from boiling), you are increasing the concentration of sugars in your wort. This is can actually be calculated. Now, to boil off 4 gallons, your boil will end up having to boil for longer than an hour. Based on your boiloff rates, you can calculate that as well.

I'm not sure how useful taking a SG reading is before the sparge. The most useful reading is preboil. That will tell you what adjustments you may or may not need to make in terms of boiloff before you start your hop additions or by actually adding more water, which is unusual.
Ok, cool. Maybe it was the concept of not boiling down all your volume to get the desired gravity that I was thinking of. I just seemed to remember hearing a podcast where they said to be sure and always have DME on hand in case you miss your target. I think I interpreted that statement incorrectly. Anyway.. thanks for all the feedback and explanations.

So, I guess bottom line is that I didnt feel that I got enough out of my grain.

I will check out that link you included.

 
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Old 03-05-2013, 12:37 AM   #10
SATXbrew
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Would be cool if that calculator also gave you expected gravity after boil..

 
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