replacing grain with extract for part of recipe

[huge1s]

My brother in law wants to come down and help me brew and split a batch. Should be fun, but I need a little help on the type of beer he wants to brew. He wants to make the Dogfish 90 minute IPA clone. Trouble is that I have a 28 (7 gallons) quart mash tun and this calls for 18.16 pounds of grain. According to the calculator on rackers.com.... I would need a mash tun to hold 7.13 gallons. Just a little over my capacity and frankly, I am not sure that my 7 gallon mash ton holds exactly 7 gallons. Besides building a bigger mash tun, what are my options here? I was thinking of substituting 2 pounds of pilsner malt with a pound of DME (numbers work out pretty close to a pound of DME to hit target OG). What kind of DME would be a good substitute? I was thinking that just a light DME would be fine and not affect flavor too much because I am still getting most of the flavor from grains. Any other options to brew this beer besides substituting a little DME?

One other add on question. This will be my first big beer and the recipe I am working off of calls for a 65% efficiency. I generally hit 78% in smaller beers, but have read that with bigger beers you should expect less efficiency. If this is true, is there a general percentage drop? I know, I know...it depends on my system and i will take careful measurements to see what my system does, but any guidance would be helpful in preventing a messed up beer. For the record, I was planning on just assuming my system will drop to 65% and if it is higher.... less DME to add to the boil.

 

[TyTanium]

Sounds like a good plan. People have done this with great success. Yup - substitute light DME for base malt. No need for amber/dark DME since you're already mashing - keep your grain bill the same, just less base malt.

Your substitution ratio depends on your efficiency, but I usually use 0.6# DME for every # of base malt. Good news is you can check your pre-boil eff. and adjust accordingly.

Also, if your DME addition is later in the boil, don't forget to adjust your math on hop utilization (since lower gravity boil)

EDIT: IME efficiency doesn't drop too drastically for larger beers. 65% should be a safe bottom, but I wouldn't be surprised if you got in the low 70's.

 

[midfielder5]

I get higher efficiency when my mash tun is full, so you won't know until you do it.
Good plan is to be ready for highs & lows, with DME or extra water to dilute if necessary.

 

[Sarrsipius]

Your plan sounds good. Since you will be replacing pilsner malt I think you should use light pilsen DME.

If you take a pre boil gravity reading you can adjust the amount of DME accordingly to achieve your target OG. (refractometer works great for this). Beer Smith can help you do the calculations.

 

[huge1s]

yeah, basically my plan was to assume 65% and have a pound of DME on hand to adjust the gravity after taking a pre-boil gravity reading. If I get better than 65%, then great. I will add the DME before I start boiling so that I don't affect the hop utilization. That is also good to know that I should not expect a big efficiency drop. If I hit 73%, I won't have to add any DME. My only concern about efficiency is that my first 3 brews were a consistent 78%-79%, but my last one was 53%. I am 90% confident that the reason for the efficiency drop was because I bought my grains from a local homebrew place (all others were from reputable online places) and they didn't crush very well. On a side note, I was back into the homebrew place to buy DME to fix my hefeweizen and told him about the apparent crush problem.... he didn't know what his mill was set at and just said "somebody probably messed with it".

 

[huge1s]

Your plan sounds good. Since you will be replacing pilsner malt I think you should use light pilsen DME.

If you take a pre boil gravity reading you can adjust the amount of DME accordingly to achieve your target OG. (refractometer works great for this). Beer Smith can help you do the calculations.

I recently had to "adjust" a broken hefeweizen and the advice from this board was that DME adds 43 points per gallon. I just did the math by hand and it came out to slightly under a pound if everything goes exactly as planned.

 

[TyTanium]

Yup - 43 points per pound per gallon is the right way to calculate (better than my 1:0.6 approx ratio above).

Also - do a forum search for late extract addition. Some claim better results by adding it at the end of the boil. I have no experience with this myself.

And a bad crush will definitely drop your efficiency. Bummer.

 

[huge1s]

thanks for the advice! Now I need to find someone that isn't out of stock on Simcoe hops

 

[huge1s]

Looks like Northern Brewer has the hops. I have never used them.... any worries about their pre-crushed grains? Figured I might as well order everything from them for this batch if they have the hops.

 

[Yooper]

Looks like Northern Brewer has the hops. I have never used them.... any worries about their pre-crushed grains? Figured I might as well order everything from them for this batch if they have the hops.

No, Northern Brewer is great. The crush gives me about 70%, if I remember correctly.

 

[RM-MN]

Why don't you just do a 4 gallon batch instead of 5 gallons and then everything will fit just fine without using extract?

 

[huge1s]

Why don't you just do a 4 gallon batch instead of 5 gallons and then everything will fit just fine without using extract?

I actually thought of that. I guess my thinking was that if I am going to spend 5 hours brewing... And a tiny bit of extract allows me to get an extra gallon of beer without impacting the flavor... Why not? With all the hops in this recipe, this will be an expensive AG brew. I would have to order the same amount of hops and a pound of DME is not that expensive.

 

[JuanMoore]

I think your plan sounds good, but for future reference if you're faced with space limitations you can just mash slightly thicker, which IMO is a good idea for higher gravity beers anyways. If you mash that same grainbill at 1.2qt/lb instead of 1.25 it will only take up 6.9 gal of space. FWIW I like to mash my higher gravity beers closer to 1qt/lb since otherwise I may not be left with enough sparge volume to get decent lauter efficiency. This is particularly true for batch sparging, since maximum efficiency occurs when the run off volumes are equal.