Question Regarding Mash Vol and efficiency when Converting a recipe

Hi

I am using a recipe the claims 80% efficiency for this 3 gal batch. Since this is my first all grain brew I am estimating it will be more like 65-70% (Fingers crossed). In order to hit the OG it required me to raise my Pale Malt from 6 lb to 11.5 lbs. If i raise the grain bill and not change the mash volumes it will change my mash thickness from about 1.25 to 0.6. My question is that if i do raise the grain bill do i need to change my mash volume as well and if so does this mean i will be making a larger then 3 gallon batch? A little confused on how to reconcile a lower estimated efficiency but maintain a decent mash thickness.

Thanks in advance and sorry if this was answered somewhere else, i couldn't find anything on this.

Are you sure you need that much grain? I'm no expert, so maybe I'm overlooking something, but it seems like you should only need to go from 6 to about 7-7.2 lbs.

You shouldn't need to double the grain to account for a slightly lower efficiency.

If you post the recipe, we can convert it to your efficiency as well as give you the volumes needed.

You need about an extra lb of grain as freisste said.

If the recipe requires 6 lbs grain at 80% efficiency, it will require 6 * 80 / 70 = 6.86 lbs grain at 70% efficiency, or 6 * 80 / 65 = 7.34 lbs grain at 65% efficiency. Keeping things simple, I would use 7 lbs grain which would require 68.6% efficiency.
It's OK to change the mash thickness slightly, but you want to keep it between 1 and 2 qt / lb. Again, keeping things simple, 7 lbs * 1.25 = 8.75 qts. I'd round that up to 9 quarts which would give you a mash thickness of 1.29 qt / lb.
If you mash with 9 qt and 7 lbs grain, you will collect about 5.5 qts of first runnings. The other 3.5 qts water will be absorbed by the grain. This is much smaller than the required batch size, so you will need to sparge with sufficient water to collect the required 3 gallon batch size plus the amount of wort that you will evaporate during the boil plus an allowance for trub if you leave the trub behind when transferring to the fermenter.

-a.

Thanks for the responses. I thought it was too high. Below is the recipe i am trying. When i put it all into Brewtarget with the published efficiency all the numbers added up, however when I changed by efficiency from 85% to 60% it estimated by OG to be 1.040 which is way off of the target. The only way i was to raise the OG was to add more grain. I had to raise by grain bill (Keeping everything in proportion) by almost two fold to reach the OG in the recipe, and now at this point it seems that for 3 gallons it would be unreasonable. I'm not quite sure what i am missing or not understanding.

I might just follow according to what is laid out and hope i come close.


Type: All Grain Date: 5/28/2011
Batch Size: 12.00 qt Boil Size: 17.74 qt
Boil Time: 90 min Equipment: Brew Pot, Full Boil All Grain (5 Gallon)
Taste Rating(out of 50): 0.0 Brewhouse Efficiency: 85.00
Ingredients

Amount Item Type % or IBU
5 lbs 12.0 oz Pale Malt (2 Row) US (2.0 SRM) Grain 81.84 %
13.0 oz Munich Malt (9.0 SRM) Grain 11.53 %
6.0 oz Carapils (1.5 SRM) Grain 5.34 %
1.5 oz Carastan (30.0 SRM) Grain 1.30 %
7.00 gm Amarillo (MoreBeer 2011) [9.30 %] (Dry Hop 10 days) Hops -
22.00 gm Centennial (MoreBeer 2011) [9.20 %] (Dry Hop 3 days) Hops -
15.00 gm Cascade (MoreBeer 2011) [6.40 %] (Dry Hop 10 days) Hops -
22.00 gm Cascade (MoreBeer 2011) [6.40 %] (Dry Hop 3 days) Hops -
15.00 gm Centennial (MoreBeer 2011) [9.20 %] (Dry Hop 10 days) Hops -
7.00 gm Simcoe (MoreBeer 2011) [12.20 %] (Dry Hop 10 days) Hops -
15.00 gm Columbus (Tomahawk) (MoreBeer 2011) [14.40 %] (60 min) Hops 44.2 IBU
26.00 gm Cascade (MoreBeer 2011) [6.40 %] (30 min) (Aroma Hop-Steep) Hops -
11.00 gm Cascade (MoreBeer 2011) [6.40 %] (30 min) Hops 11.1 IBU
26.00 gm Centennial (MoreBeer 2011) [9.20 %] (30 min) (Aroma Hop-Steep) Hops -
9.00 gm Centennial (MoreBeer 2011) [9.20 %] (30 min) Hops 13.0 IBU
1.00 gm Calcium Chloride (Mash 60.0 min) Misc
1.00 items Whirlfloc Tablet (Boil 15.0 min) Misc
4.00 gm Gypsum (Calcium Sulfate) (Mash 60.0 min) Misc
1 Pkgs English Ale (White Labs #WLP002) Yeast-Ale
Beer Profile
Est Original Gravity: 1.072 SG Measured Original Gravity: 1.072 SG
Est Final Gravity: 1.014 SG Measured Final Gravity: 1.014 SG
Estimated Alcohol by Vol: 7.64 % Actual Alcohol by Vol: 7.58 %
Bitterness: 68.3 IBU Calories: 325 cal/pint
Est Color: 5.9 SRM Color:
Color
Mash Profile
Mash Name:
BIAB Double Sparge Total Grain Weight:
7.03 lb
Sparge Water:
11.11 qt Grain Temperature:
70.0 F
Sparge Temperature:
168.0 F TunTemperature:
146.0 F
Adjust Temp for Equipment:
TRUE Mash PH:
5.4 PH

BIAB Double Sparge
Step Time Name Description Step Temp
55 min Mash In Add 8.00 qt of water at 157.0 F 145.0 F
20 min Step Add 2.00 qt of water at 202.9 F 155.0 F

Well the first numbers we gave was when you wanted to go from 80% to 65-70% efficiency. Now you're going from 85% to 60% so you'll need about 1/3 more grain. Definitely not double the grainbill, though.

When I plug your numbers into Beersmith they don't match yours. I wonder if something in the settings you have like trub loss could be throwing off your brewhouse efficiency making it quite a bit different from mash efficiency. The issue of brewhouse vs. mash efficiency is confusing in Beersmith and I find brewhouse hard to use. I personally set the trub loss to zero and then instead adjust up the batch size to account for losses. This way mash effiiciency equals the brewhouse effiiciency, and it's easier to manipulate and hit my numbers . If you have no idea what I'm talking about I can point you to the places in the Beersmith forums that explain.

At any rate, I get the following grainbill at 60% efficiency hitting your target gravity, and it keeps the percentages the same (and as a double check, is about 1/3 more grain than your original recipe) :

7 lbs 12.0 oz Pale Ale 81.6 %
1 lbs 2.0 oz Munich Malt 11.8 %
8.0 oz Cara-Pils/Dextrine 5.3 %
2.0 oz Carastan 1.3 %

EDIT: sorry, I haven't had my full dose of coffee yet and I see you're using Brewtarget but I read Beersmith. Sorry can't help you with the settings but pretty sure my numbers are right.

chickypad said:

When I plug your numbers into Beersmith they don't match yours.

At any rate, I get the following grainbill at 60% efficiency hitting your target gravity, and it keeps the percentages the same (and as a double check, is about 1/3 more grain than your original recipe) :

7 lbs 12.0 oz Pale Ale 81.6 %
1 lbs 2.0 oz Munich Malt 11.8 %
8.0 oz Cara-Pils/Dextrine 5.3 %
2.0 oz Carastan 1.3 %

Click to expand...

That's strange. I plugged the numbers into both Beersmith and Promash, and both estimated an OG of 1.072 assuming 85% efficiency.

I then scaled the recipe for 60% efficiency, and got the following grain bills:
Beersmith:
8 lb 2.3 oz Pale Malt (81.85%)
1 lb 2.4 oz Munich Malt (11.53%)
8.5 oz Cara-Pils (5.34%)
2 oz Carastan (1.28%)

Promash:
8 lb 2.33 oz Pale Malt 36 pppg (81.8%)
1 lb 2.43 oz Munich Malt 37 pppg (11.6%)
8.5 oz Cara-Pils 34 pppg (5.3%)
2.13 oz Carastan 35 pppg (1.3%)

I then used a calculator to estimate the OG just to make sure there was nothing in the Beersmith or Promash profiles that could cause a wrong reading. The calculator gave an estimate of 1.071, but I rounded the weights down, so I think that is acceptable.

Perhaps chickypad's computer needs a caffeine fix as well.

-a.

ajf said:

Perhaps chickypad's computer needs a caffeine fix as well.

Click to expand...

Ha, could be! Sorry, though, I meant that the OP's calculation of 1.040 didn't match mine when I took his (her?) grainbill and changed it to 60% efficiency - I got something like 1.053.

I did just notice for some reason with the original grainbill at 85% I get 1.075 in Beersmith. Might be I've plugged in some non-standard numbers on some of the grains in my inventory. Looks like we're pretty close though ajf, you have the new recipe at 9lb 15 oz grain and I've got 9 lb 8 oz - I also did a little rounding down.

Then again, may not want to listen to me. I'm fully caffeinated now but also about a beer and half into brew day!!



Edit: Okay, not that drunk yet after all. That was it, I had a particular English pale malt that was 1.038 potential in my inventory that I accidentally plugged in. With regular pale malt at 1.036 my numbers now match yours ajf. Always makes me feel better when the math works.