Irish Red Extract to Partial Mash

Hey all,

My LHBS has an extract recipe for an Irish Red that goes as follows:

BeerSmith Recipe Printout - http://www.beersmith.com
Recipe: Irish Hills Red
Brewer: Brian Moore
Asst Brewer:
Style: Irish Red Ale
TYPE: Extract
Taste: (35.0)

Recipe Specifications
--------------------------
Batch Size: 5.00 gal
Boil Size: 2.50 gal
Estimated OG: 1.055 SG
Estimated Color: 15.0 SRM
Estimated IBU: 12.0 IBU
Brewhouse Efficiency: - %
Boil Time: 60 Minutes

Ingredients:
------------
Amount Item Type % or IBU
6 lbs DME Golden Light (Briess) (4.0 SRM) Dry Extract 80.00 %
1 lbs Caramel/Crystal Malt -120L (120.0 SRM) Grain 13.33 %
8.0 oz Cara-Pils/Dextrine (2.0 SRM) Grain 6.67 %
1.00 oz Goldings, East Kent [5.00 %] (60 min) Hops 10.0 IBU
1.00 oz Goldings, East Kent [5.00 %] (5 min) Hops 2.0 IBU
1 Pkgs Burton Ale (White Labs #WLP023) Yeast-Ale


Mash Schedule: None
Total Grain Weight: 1.50 lb
----------------------------
Steep grains as desired (30-60 minutes)

I brewed this and I really liked it. I am currently trying to do as many partial mashes as I can, to get good at the technique. I would like to brew this beer only using the partial mashing technique, instead of just extract. Using BeerSmtih I came up with the following:

BeerSmith Recipe Printout - http://www.beersmith.com
Recipe: Irish Hills Red Partial
Brewer: Brian Moore
Asst Brewer:
Style: Irish Red Ale
TYPE: Partial Mash
Taste: (35.0)

Recipe Specifications
--------------------------
Batch Size: 5.00 gal
Boil Size: 2.98 gal
Estimated OG: 1.056 SG
Estimated Color: 14.8 SRM
Estimated IBU: 19.0 IBU
Brewhouse Efficiency: 75.00 %
Boil Time: 60 Minutes

Ingredients:
------------
Amount Item Type % or IBU
3 lbs DME Golden Light (Briess) (4.0 SRM) Dry Extract 41.38 %
2 lbs DME Golden Light (Briess) (4.0 SRM) Dry Extract 27.59 %
1 lbs Caramel/Crystal Malt -120L (120.0 SRM) Grain 13.79 %
12.0 oz Pale Malt (2 Row) US (2.0 SRM) Grain 10.34 %
8.0 oz Cara-Pils/Dextrine (2.0 SRM) Grain 6.90 %
1.00 oz Goldings, East Kent [5.00 %] (60 min) Hops 11.6 IBU
1.00 oz Goldings, East Kent [5.00 %] (5 min) Hops 2.3 IBU
1 Pkgs Burton Ale (White Labs #WLP023) Yeast-Ale


Mash Schedule: Single Infusion, Full Body, Batch Sparge
Total Grain Weight: 2.25 lb
----------------------------
Single Infusion, Full Body, Batch Sparge
Step Time Name Description Step Temp
45 min Mash In Add 2.81 qt of water at 172.5 F 158.0 F


Notes:
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I am using late extract addition which boosted my IBU's from 12 to 19, which I am ok with. As this is my first attempt at converting using BeerSmith, I just want to get some opinons to see if ya'll think this looks ok.

Thanks in advance,
Brian

I don't think the grain bill is comparable in your partial mash. Basically, you've taken 1 pound of DME (which contributes about 43 GU to your beer) and substituted 12oz of pale malt. One pound of pale malt has about 36 GU, so your 12 oz only contains a MAXIMUM of 27 GU. Then, when you factor in your brewhouse efficiency (75% I see in your notes), you're only going to get about 21 GU from the pale malt. You actually need a little more than 1.5# of pale malt to sub for 1# of DME.

I think it's a great idea to take recipes you like and rebrew them as partial mashes as a learning experience. My only advice (besides making sure you're correctly subbing ingredients) is to mash a little more grains - maybe 4-5 pounds. This will give you a better sense of the mashing process. When you're only mashing a couple pounds, you're basically just doing an extract batch with specialty steep that takes longer. But you gotta start somewhere!

If you're conducting a partial mash, why not mash as much grain as your mashing system will hold? Simply put, I don't think 20 ounces of grain is really worth mashing; if you can mash 4-5 lbs, you'll have a much easier time of it. Larger masses of mash hold temperature more readily; smaller masses lose heat very rapidly, even in an insulated vessel.

I probably wouldn't even bother with software for this one. I'd simply sub as much pale malt for as much extract as my equipment would hold, using the following ratio:

1 lb pale malt = 0.75 lbs. extract syrup = 0.6 lbs. extract powder

My partial-mash mash tun holds five pounds of grain. So I'd mash 4 lbs of pale malt plus the pound of 120L Crystal (omitting the CaraPils, because you really don't need it). That means I can reduce my extract syrup by 3 lbs. and DME by 2.4 lbs. Of course, it's always wise to keep some extra DME on hand in case of mash-efficiency difficulties, so you can ensure your desired OG is met.

Mashing that amount also means you can conduct the boil with a larger volume without adding any extract at all until quite late in the boil and still have a good-enough kettle gravity for good hops isomerization. I generally get ~3 gallons US into the kettle with 5 lbs of grain in the tun at a decent medium gravity.

YMMV!

Bob

+1 on mashing as much grain as possible. The purpose of the PM technique is to do just that and make up the rest with DME. Whats your max grain capacity?

Thanks so much for the quick responses. Redoing what I had with both your sugestions (which I totally see the logic). I now come up with a pretty simple grain bill (if I did my math right)

3 lbs 9.6 oz DME Golden Light (Briess) (4.0 SRM) Dry Extract 41.86 %
4 lbs Pale Malt (2 Row) US (2.0 SRM) Grain 46.51 %
1 lbs Caramel/Crystal Malt -120L (120.0 SRM) Grain 11.63 %

Using 1.25qts/lb I come up with 6.25qts or 1.5625 gallons of water for my mash tun. I am using a 30 quart Alimunum Pot as my mash tun, so I think I have enough room for 5 lbs of grain and water. I come up with a loss of .5 gallons during the mash. So remaining wort after mash should be 1.0625 gallons. Thus if I want a 3 gallon boil I need to have 1.9375 gallons in my boil kettle, using Deathbrewers "Stove Top Partial Mash" technique. Does this all sound right?

Thanks again,

I think that'll work, though if you don't get 75% efficiency, you won't hit your OG. But you'll definitely be able to fit it all. I'd recommend at least 1.5 qts/lb - you'll get better efficiency this way.

And don't hesitate to sparge with more water and do a full boil (or close to it)

Thanks! I struggle to get 3 gallons to boil..so I am pretty maxed out there. But I will do 1.5 qt/lbs and see how it goes.