Weezy
Well-Known Member
Caveat: This article is my opinion, based on my personal experiences as a homebrewer. I am not an expert. YMMV. RDWHAHB.….and whatever other acronyms might seem appropriate.
Note too that the grain and hop weight and percentages used here are very rough numbers just to illustrate the point.
Threads pop-up all the time with people considering making a session (low gravity beer) or imperial (high gravity beer) version of some beer recipe or general style. I’ve spent a lot of time on session beers and the occasional high gravity ale as well. This article intends to share my experience and ideas in modifying an otherwise normal recipe (say, 1.050-1.070 OG beer) to make it a good session or imperial beer. I’ll be discussing this in three sections: (1) How to adjusting grain percentages, (2) How to adjust hop quantities, and (3) adding or subtracting grains or adjuncts to support the flavor and mouthfeel.
How to adjusting grain percentages
Let’s say your favorite IPA recipe is a 6% beer (OG about 1.060) and your malt bill is:
Regular IPA (1.060)
U.S. Pale Malt 10 lbs. (90%)
Crystal 60 0.5 lbs. (5%)
Carapils/Dextrin Malt 0.5 lbs. (5%)
And you want to make a low alcohol, session version. The first inclination is to jump into your software and ratchet down the OG to, say, 1.045, and let’er rip. Lowering the OG in your software will maintain the ratio of grains (i.e. percentages) and simply adjust the grain weight to get to the desired OG. You’ll end up with something like this:
Session IPA (1.045)
U.S. Pale Malt 7.5 lbs. (90%)
Crystal 60 0.4 lbs. (5%)
Carapils/Dextrin Malt 0.4 lbs. (5%)
Makes sense, right? You need less malt to get to the lower gravity. Yep. But…doing this, and brewing this beer, isn’t much different than just watering down the original 1.060. Imagine taking your favorite IPA recipe and adding a gallon of water to it. You end up with a watered down flavor effect. Not good.
Similarly, say you want to make an Imperial IPA out of that same beer. Again, go into your brew software and ratchet up the OG to 1.085, and you get something close to:
Imperial IPA (1.085)
U.S. Pale Malt 13.5 lbs. (90%)
Crystal 60 0.9 lbs. (5%)
Carapils/Dextrin Malt 0.9 lbs. (5%)
Here, you’re facing the opposite result. You’ve just added 0.8 lbs more specialty malt to your favorite IPA recipe. Your IIPA is probably going to taste sweeter and richer than you’ll like.
What I’ve found to work is to (1) maintain the specialty malt weights, and (2) adjust only the base grain weight to account for the desired change (increase or decrease) in OG. Doing this maintains the same flavor and mouthfeel contribution from the specialty malts/adjuncts, which you don’t want to vary much from big to small versions of the beer. So, our session IPA should look more like this:
Fixed Session IPA (1.045)
U.S. Pale Malt 7.2 lbs. (88%)
Crystal 60 0.5 lbs. (6%)
Carapils/Dextrin Malt 0.5 lbs. (6%)
Note the specialty malt weights have stayed at ½ pound, and to account for that the base grain weight is actually lower than the previous session IPA estimate when we just ratched down the OG in the software. We end up with a small increase in the percentage contribution of the specialty grains (and a corresponding reduction in the base grain percentage).
For our IIPA:
Fixed Imperial IPA (1.085)
U.S. Pale Malt 14.4 lbs. (94%)
Crystal 60 0.5 lbs. (3%)
Carapils/Dextrin Malt 0.5 lbs. (3%)
A similar result is seen to the fixed session beer. Note the more drastic percentage swing though. Keeping the specialty grains at ½ lb. each forces the base grain weight up quite a bit vs. the previous IIPA estimate. Don’t let the percentage number scare you because the flavor contribution from the critical specialty grains is going to be the same as the regular beer simply because the weight is the same.
How to adjust hop quantities
Adjusting hop quantities can be as equally problematic as grains. If you keep the same amount of hops in the session ale, it might come out too bitter and/or or just overpower the malt contribution. It’s the same thing with the IIPA; if you keep the hop schedule from 1.060 when you brew the 1.085 beer, that may not be enough hops and the malt may dominate the beer. This is even more complex when you factor in the large, late hop additions we’re becoming accustomed to for the massive aroma flavor they provide. As far as adjusting hops, let’s start by talking about bitterness and then we’ll talk about flavor & aroma separately, later.
Adjusting Hop Bitterness - This is the easy part. There is a sure fire tool that we can use to adjust our bitterness to maintain a similar balance between different strength beers. The tool, which I first found in Ray Daniel’s book, Designing Great Beer, is the BU:GU ratio (Bitterness Units to Gravity Units ratio). It’s a very simple relationship between IBUs and OG. Say you have a 1.050 beer with 50 IBUs. The Bitterness Units (BU) equals your IBUs; BU=50. The Gravity Units is the numbers right of the decimal as a whole number (GU=50). So the BU:GU ration of the beer is 50 ÷ 50 = 1. A not so hoppy beer might have a BU:GU in the 0.4 to 0.6 range. A very hoppy beer will be >1.5. You get the idea. So, like how we maintained the weight of the specialty grains, for hops we want to maintain the BU:GU ratio to maintain the same balance of bitterness to malt. Here’s how that relates in an example:
Regular Beer: OG 1.060, IBU 50, BU:GU = (50 ÷ 60) = 0.83
Session Beer: OG 1.045, BU:GU 0.83, therefore IBUs must be (45 x 0.83) = 37
Imperial Beer: OG 1.085, BU:GU 0.83, IBU = (85 x 0.83) = 71
Adjusting Flavor & Aroma Hop Additions – This is difficult to quantify because it comes down to your own tastes and the specific beer, but what I generally do is simply cut, for session beers, or increase, for imperial beers, my dosage rate of late hops and dry hops proportional to the OG. For an IPA, I typically dose hopstand hops at 21 grams/gallon. For a session version I’d cut that to 16 grams per gallon (based on ratio of the gravity units from the OGs = 1.045 & 1.060 = 45 ÷ 60 = 75%). Similarly for IIPA, I’d increase the dosage ratio proportionally to 30 grams/gallon (85 ÷ 60 = 142%). You may prefer to do more or less, based on the individual beer and what you want out of it, and after having tried it.
Further Tweaks – Other Grains and Adjuncts
So, let’s say you sessionized that favorite IPA and it’s lacking. Maybe it tastes ok but it’s seems thin or watery? Or that IIPA version is still just too malty?
To enhance session beers, here’s some quick thoughts:
For imperial beers:
And to wrap up, these are techniques that work for me. If nothing else, I hope these ideas make you think about your recipe formulation. I do think formulating recipes in terms of percentages instead of weight is wise, because it’s easy to get in a rut of thinking in terms of ½ lb of this and 1 lb of that, when your beer might really shine if you go from 5% to 4% or 3% of that one malt. Similarly, I feel planning hops in terms of grams per gallon is a nice, generic approach.
Cheers!
Note too that the grain and hop weight and percentages used here are very rough numbers just to illustrate the point.
Threads pop-up all the time with people considering making a session (low gravity beer) or imperial (high gravity beer) version of some beer recipe or general style. I’ve spent a lot of time on session beers and the occasional high gravity ale as well. This article intends to share my experience and ideas in modifying an otherwise normal recipe (say, 1.050-1.070 OG beer) to make it a good session or imperial beer. I’ll be discussing this in three sections: (1) How to adjusting grain percentages, (2) How to adjust hop quantities, and (3) adding or subtracting grains or adjuncts to support the flavor and mouthfeel.
How to adjusting grain percentages
Let’s say your favorite IPA recipe is a 6% beer (OG about 1.060) and your malt bill is:
Regular IPA (1.060)
U.S. Pale Malt 10 lbs. (90%)
Crystal 60 0.5 lbs. (5%)
Carapils/Dextrin Malt 0.5 lbs. (5%)
And you want to make a low alcohol, session version. The first inclination is to jump into your software and ratchet down the OG to, say, 1.045, and let’er rip. Lowering the OG in your software will maintain the ratio of grains (i.e. percentages) and simply adjust the grain weight to get to the desired OG. You’ll end up with something like this:
Session IPA (1.045)
U.S. Pale Malt 7.5 lbs. (90%)
Crystal 60 0.4 lbs. (5%)
Carapils/Dextrin Malt 0.4 lbs. (5%)
Makes sense, right? You need less malt to get to the lower gravity. Yep. But…doing this, and brewing this beer, isn’t much different than just watering down the original 1.060. Imagine taking your favorite IPA recipe and adding a gallon of water to it. You end up with a watered down flavor effect. Not good.
Similarly, say you want to make an Imperial IPA out of that same beer. Again, go into your brew software and ratchet up the OG to 1.085, and you get something close to:
Imperial IPA (1.085)
U.S. Pale Malt 13.5 lbs. (90%)
Crystal 60 0.9 lbs. (5%)
Carapils/Dextrin Malt 0.9 lbs. (5%)
Here, you’re facing the opposite result. You’ve just added 0.8 lbs more specialty malt to your favorite IPA recipe. Your IIPA is probably going to taste sweeter and richer than you’ll like.
What I’ve found to work is to (1) maintain the specialty malt weights, and (2) adjust only the base grain weight to account for the desired change (increase or decrease) in OG. Doing this maintains the same flavor and mouthfeel contribution from the specialty malts/adjuncts, which you don’t want to vary much from big to small versions of the beer. So, our session IPA should look more like this:
Fixed Session IPA (1.045)
U.S. Pale Malt 7.2 lbs. (88%)
Crystal 60 0.5 lbs. (6%)
Carapils/Dextrin Malt 0.5 lbs. (6%)
Note the specialty malt weights have stayed at ½ pound, and to account for that the base grain weight is actually lower than the previous session IPA estimate when we just ratched down the OG in the software. We end up with a small increase in the percentage contribution of the specialty grains (and a corresponding reduction in the base grain percentage).
For our IIPA:
Fixed Imperial IPA (1.085)
U.S. Pale Malt 14.4 lbs. (94%)
Crystal 60 0.5 lbs. (3%)
Carapils/Dextrin Malt 0.5 lbs. (3%)
A similar result is seen to the fixed session beer. Note the more drastic percentage swing though. Keeping the specialty grains at ½ lb. each forces the base grain weight up quite a bit vs. the previous IIPA estimate. Don’t let the percentage number scare you because the flavor contribution from the critical specialty grains is going to be the same as the regular beer simply because the weight is the same.
How to adjust hop quantities
Adjusting hop quantities can be as equally problematic as grains. If you keep the same amount of hops in the session ale, it might come out too bitter and/or or just overpower the malt contribution. It’s the same thing with the IIPA; if you keep the hop schedule from 1.060 when you brew the 1.085 beer, that may not be enough hops and the malt may dominate the beer. This is even more complex when you factor in the large, late hop additions we’re becoming accustomed to for the massive aroma flavor they provide. As far as adjusting hops, let’s start by talking about bitterness and then we’ll talk about flavor & aroma separately, later.
Adjusting Hop Bitterness - This is the easy part. There is a sure fire tool that we can use to adjust our bitterness to maintain a similar balance between different strength beers. The tool, which I first found in Ray Daniel’s book, Designing Great Beer, is the BU:GU ratio (Bitterness Units to Gravity Units ratio). It’s a very simple relationship between IBUs and OG. Say you have a 1.050 beer with 50 IBUs. The Bitterness Units (BU) equals your IBUs; BU=50. The Gravity Units is the numbers right of the decimal as a whole number (GU=50). So the BU:GU ration of the beer is 50 ÷ 50 = 1. A not so hoppy beer might have a BU:GU in the 0.4 to 0.6 range. A very hoppy beer will be >1.5. You get the idea. So, like how we maintained the weight of the specialty grains, for hops we want to maintain the BU:GU ratio to maintain the same balance of bitterness to malt. Here’s how that relates in an example:
Regular Beer: OG 1.060, IBU 50, BU:GU = (50 ÷ 60) = 0.83
Session Beer: OG 1.045, BU:GU 0.83, therefore IBUs must be (45 x 0.83) = 37
Imperial Beer: OG 1.085, BU:GU 0.83, IBU = (85 x 0.83) = 71
Adjusting Flavor & Aroma Hop Additions – This is difficult to quantify because it comes down to your own tastes and the specific beer, but what I generally do is simply cut, for session beers, or increase, for imperial beers, my dosage rate of late hops and dry hops proportional to the OG. For an IPA, I typically dose hopstand hops at 21 grams/gallon. For a session version I’d cut that to 16 grams per gallon (based on ratio of the gravity units from the OGs = 1.045 & 1.060 = 45 ÷ 60 = 75%). Similarly for IIPA, I’d increase the dosage ratio proportionally to 30 grams/gallon (85 ÷ 60 = 142%). You may prefer to do more or less, based on the individual beer and what you want out of it, and after having tried it.
Further Tweaks – Other Grains and Adjuncts
So, let’s say you sessionized that favorite IPA and it’s lacking. Maybe it tastes ok but it’s seems thin or watery? Or that IIPA version is still just too malty?
To enhance session beers, here’s some quick thoughts:
- Consider adding modest flavor body builders like dextrin malts (<2L), Carafoam, torrified wheat, flaked wheat, flaked barley, flaked outs. Start around 3% (taking that 3% away from your base grain percentage, not the specialty grains). I sue a lot of flaked barley and Carafoam.
- Similarly, try using a richer but similar malt for all or a portion of the base grain bill. If you're using 80% pale malt, maybe try 50% pale and 30% pale ale.
- Mash slightly higher to enhance unfermentables.
- Add Calcium Chloride to enhance the malts.
- Try a less attenuative yeast.
For imperial beers:
- Consider using flaked rice and/or sugar at 3% (up to 10%, each, for extremely big beers).
- Mash lower, even in the mid 140s.
- Use highly attenuative yeasts.
And to wrap up, these are techniques that work for me. If nothing else, I hope these ideas make you think about your recipe formulation. I do think formulating recipes in terms of percentages instead of weight is wise, because it’s easy to get in a rut of thinking in terms of ½ lb of this and 1 lb of that, when your beer might really shine if you go from 5% to 4% or 3% of that one malt. Similarly, I feel planning hops in terms of grams per gallon is a nice, generic approach.
Cheers!