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BlackDuck

BU:GU Ratio

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A few weeks ago we had a thread going about BU:GU ratio's. In working on a recipe last night I referenced back on that thread and still found myself slightly confused, so I started searching the web and found two good site's. I thought I would share for everyone, since they both helped me understand and figure my ratio.

The first site is what I thought was a good explanation along with a reference of ratio's for certain styles of beer:
http://finnhillbrewing.blogspot.com/2011/04/bugu-ratios.html

The second site was a calculator to help figure the actual ratio:
http://www.beermath.com/pages/bu_gu_calculator.html

Like I said...Both these sites helped me so I thought I would pass it along for everyone else!!

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Thankyou for that. I have been wondering about the first one. The second one is built into my brewing software.

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BlackDuck~

These are great.

***But*** I think a disclaimer should be put that everyone's tastes vary. Let's take one example, the American Brown Ale. According to the finnhillbrewing information, they list that an American Brown Ale's BU:GU ratio would be -- American Brown 0.95 . This would make it very heavy on the HOPPY side. HOWEVER...when you look at the BJCP style guidelines...the vitals for an American Brown Ale are:

Vital Statistics: OG: 1.045 – 1.060
IBUs: 20 – 40 FG: 1.010 – 1.016
SRM: 18 – 35 ABV: 4.3 – 6.2%

Yes...you could produce an American Brown with an OG of 1.045 and an IBU of 40 and get a 0.95 BU:GU ratio. But you could also easily tailor your beer to be a 1.058 with a 30 IBUs (0.52).

Furthermore, the BJCP suggests that:
Flavor: Medium to high malty flavor (often with caramel, toasty and/or chocolate flavors), with medium to medium-high bitterness. The medium to medium-dry finish provides an aftertaste having both malt and hops. Hop flavor can be light to moderate, and may optionally have a citrusy character. Very low to moderate fruity esters. Moderately low to no diacetyl.

The point I'm getting to is that the guidelines do not dictate that 0.95 is the only way to get there.

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"Christ872" post=250917 said:

BlackDuck~

they list that an American Brown Ale's BU:GU ratio would be -- American Brown 0.95 . This would make it very heavily on the malty side

You mean hoppy side. ;)


Edit: I like the graph in the 1st link, I think it goes higher on the OG than the one around here...have to check (nope, its the same, maybe the one I have saved on my home pc needs to be updated)

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"mnstarzz13" post=250919 said:

"Christ872" post=250917 said:

BlackDuck~

they list that an American Brown Ale's BU:GU ratio would be -- American Brown 0.95 . This would make it very heavily on the malty side

You mean hoppy side. ;)

mnstarzz13~

Nice catch. Thanks. I'll edit. That is what I meant.

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I am glad to see this topic come up again because it is still causing me some confusion. I tried to work through a thread on this some time ago and kind of got dope-slapped because I just couldn’t seem to catch on. In reality I think I failed to make my question clear enough to be understood. (That’s not to say I won’t get dope-slapped again this time though.)

The following two paragraphs are the instructions for calculating IBU using QBrew taken from Screwy Brewer’s website. (http://www.thescrewybrewer.com/2010/09/qbrew-homebrewers-recipe-calculator.html)

“Special Note When Entering Hop Additions: If you want to add up all the IBUs for your hop additions enter all your hops before adding in your grains. As you add in your grain additions qBrew's built in formula will begin subtracting the malt's sweetness from the hop's bitterness in order to indicate the balance of the recipe. The formula qBrew uses to calculate this balance is the same one used by my Bitterness Balance Calculator to display the recipe's overall balance between hopped bitterness and malt sweetness in a hopped beer style.

The formula takes into consideration the beer's original gravity, actual attenuation and bittering level but does not take into account phenol, ester or other complexities. The beer drinker should use the desired IBUs as a reference point and decide for themselves what they consider to be balanced.”

If I follow this method for a recent recipe of mine I get two drastically different IBU results as shown below. 53 versus 26.

Which of these two IBU numbers should be used to compare the recipe to the BJCP Style Guidelines? In this case it determines whether or not the style guideline is met.


[attachment=7693]IBU-BUGU-1.jpg[/attachment]


[attachment=7694]IBU-BUGU-2.jpg[/attachment]


[attachment=7695]IBU-BUGU-3.jpg[/attachment]

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StatnBrew...jut a quick question on your illustrations..The top screenshot looks a little weird. The Recipe Gravity and the Estimated Final Gravity are both at 1.000, the ABV is at 0.0 and the color is at 0. Looks like something didn't work right when you were entering your numbers.

But you second screenshot has all that info on it.

EDIT
StatsnBrew...I see why your numbers are off. There are no weights entered in the Grains tab on the first screenshot. That's what is throwing your IBU's off.

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I think your looking at it wrong StatsnBrew, the picture chart is designed for AFTER malt not Before malt.

A second chart would be needed to show the before.

You can not add 53 at 1.000 and just mark at the 1.080 line since it is NOT 53 at 1.080 it is 53 at 1.000.

The graph would be 53 @ 1.000 to 26 @1.080 then a line between to show the effect as the Gravity rises

--- edit ---

This allows you to adjust the final gravity to make the beer Malty (20-35) or Balanced (35-42) or Hoppy (43+) after grains are added

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"BlackDuck" post=250946 said:

StatnBrew...jut a quick question on your illustrations..The top screenshot looks a little weird. The Recipe Gravity and the Estimated Final Gravity are both at 1.000, the ABV is at 0.0 and the color is at 0. Looks like something didn't work right when you were entering your numbers.

But you second screenshot has all that info on it.

EDIT
StatsnBrew...I see why your numbers are off. There are no weights entered in the Grains tab on the first screenshot. That's what is throwing your IBU's off.

right, hes showing how the IBU's are higher with no malt.

I agree with Trollby.

I'll add that qbrew is assuming each recipe is made with a full vol boil using all those malts. As you add or subtract malt, your utilization will change affecting IBU's extracted. If your only going to boil some of the water and malt it gets a bit more tricky to accuratly calc IBU's

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"mnstarzz13" post=250951 said:

"BlackDuck" post=250946 said:

StatnBrew...jut a quick question on your illustrations..The top screenshot looks a little weird. The Recipe Gravity and the Estimated Final Gravity are both at 1.000, the ABV is at 0.0 and the color is at 0. Looks like something didn't work right when you were entering your numbers.

But you second screenshot has all that info on it.

EDIT
StatsnBrew...I see why your numbers are off. There are no weights entered in the Grains tab on the first screenshot. That's what is throwing your IBU's off.

right, hes showing how the IBU's are higher with no malt.

I agree with Trollby.

I'll add that qbrew is assuming each recipe is made with a full vol boil using all those malts. As you add or subtract malt, your utilization will change affecting IBU's extracted. If your only going to boil some of the water and malt it gets a bit more tricky to accuratly calc IBU's

Thanks for the replies. I think you guys may have set me straight here. Please correct me if I'm wrong...

If I am designing a recipe in QBrew to meet a specific BJCP style the IBU number I should use to compare to the guidelines is the one that is adjusted for the malt's sweetness. In my example that would be 26 not 53. Is that correct?

Note that I knowingly did the first one with all the grains set to zero to get the number Screwy Brewer refers to... “Special Note When Entering Hop Additions: If you want to add up all the IBUs for your hop additions enter all your hops before adding in your grains. As you add in your grain additions qBrew's built in formula will begin subtracting the malt's sweetness from the hop's bitterness in order to indicate the balance of the recipe..."

Not sure why I am so wrapped around the axle when it come to BJCP style guidelines. I have no intention of competing but I do want to understand the rules of the game.

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Maybe I'm oversimplifying what Stats is trying to get at here, but this is the way I understand it. I'm probably also saying what everyone else is, but in a dumber way.

Getting the hops number with no malt is basically what the bitterness of hops would be all by themselves. So, the first number with no malt added would be the bitterness of hop water.

The BU:GU ratio seems to be a faulty one if you have to take numbers from different places. Occam's Razor, I guess, is what I'm saying.

The BU:GU ratio from the first screenshot would be 53:00.
The ratio from the second would be 26:80.

EDIT:

Stats reposted after I wrote my whole thinger.

"StatsnBrew" post=250972 said:

If I am designing a recipe in QBrew to meet a specific BJCP style the IBU number I should use to compare to the guidelines is the one that is adjusted for the malt's sweetness. In my example that would be 26 not 53. Is that correct?

Yes, that is my understanding.

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Thanks for the replies. I think you guys may have set me straight here. Please correct me if I'm wrong...

If I am designing a recipe in QBrew to meet a specific BJCP style the IBU number I should use to compare to the guidelines is the one that is adjusted for the malt's sweetness. In my example that would be 26 not 53. Is that correct?

Note that I knowingly did the first one with all the grains set to zero to get the number Screwy Brewer refers to... “Special Note When Entering Hop Additions: If you want to add up all the IBUs for your hop additions enter all your hops before adding in your grains. As you add in your grain additions qBrew's built in formula will begin subtracting the malt's sweetness from the hop's bitterness in order to indicate the balance of the recipe..."

I believe you are correct...use the 26 and not the 53.

The directions on Screwys site is just telling you to add the items in your Hop side before the Grain side. This allows the program to figure as close to accurate as possible. But you still need to add all your grain information to get the "net" IBU number.

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Maybe screwey will pipe in. I am not sure why one would want to know the IBU's given with no malt present because there is always malt present in beer, so dont worry, i too dont get the importance behind that statement.

Maybe its a note only about HME's. Since HME's are not boiled and the IBU's are already "fixed" numbers in s set volume, you'd not wat to decrease those #'s in qbrew.

If you have a recipe with 1 can HME and 1 UME with an oz of hops boiled for 30min, you first enter the HME in (to both the grains and hops tab) to know its IBU's alone. Then remove the HME from the hops tab and add all other ingrediants to determine the IBU's provided. Note the IBU's and manually add the IBU's from the HME and thats your total. Sincee thee HME does not get boiled, the IBU's will not change. Their perceived bitterness will change by adding more grains but not the actual IBU's because the IBU's are not being extracted on brew day, they were infused at the factory.

Hope that helps but I worry I talked in circles

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Hmm hopefully Screwy can comment but I've never done it like that. Calculating IBUs independently of the gravity and boil size is not really useful AFAIK. Because it's all theoretical. If you boil your hops in a 1 gallon, 1.100 wort and then dilute to 2.5 you'll have a lot fewer IBUs than if you did a full volume boil at 1.050, for any amount of hops. So it's pretty essential to take that into account. It's not that more malt lowers the IBUs per se, but boiling in a more concentrated wort can.

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I think some clarification is in order.

If you're using HMEs, adding more malt will not lower the IBUs. The IBUs are set at the factory when the HME is canned. However, the calculation performed by Qbrew uses a standard formula and assumes that the hops are boiled in all the malt in a full volume boil. Some malt is required in the boil in order to extract the bitterness from the hops, but at a certain point, the utilization begins to drop.

When you enter an HME in Qbrew with a 5 minute boil, you get the correct IBUs. If you then add a bunch of additional malt, the IBUs will drop. This is not because the IBUs actually drop, but because the calculation Qbrew uses makes some incorrect assumptions.

Also, hops utilization does not always follow the formulas perfectly. There are variations based on a lot of different things that are not in the formula. I think that's why many breweries and makers of hopped extract use a combination of hops and hop extracts. They do the hop boil, measure the bitterness, then adjust accordingly with hop extract to get to the point where they want to be. I may be wrong about that, since I'm just speculating, but it makes sense to me that they would do something like that.

I live at an elevation, so the calculation is always wrong for me since water boils at 209F here. There's an adjustment factor that I can use to correct this, but I don't bother, because I use the IBU calculation as more of a guideline than an actual rule (that last part should be read in a pirate's voice ala POTC).

Another thing to consider is that the BU:GU ratio is really just a starting point. Depending on your ingredients, the OG reading can be a little misleading. For example, if you've got a lot of steeping grains and/or you mashed at a higher temperature and/or used some nonfermentable sugar like lactose, you're going to end up with more sugar that didn't ferment, so there will be more residual sweetness. Conversely, if you mashed at a lower temperature and/or used a fair amount of adjuncts and/or used a yeast that attenuates aggressively, you'll end up with fewer unfermented sugars and more bitterness than the ratio would indicate.

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Thank you all. This was very helpful discussion for this beginner trying to brew like a science project.

I feel like I made the right decision on that Imperial Stout a few weeks ago by just noting the numbers and brewing it. It was really tasty going into the bottles. Of course, to follow the rules I shouldn't pop a carbonated bottle until October. But we all know I'm going to cheat on that rule! Soon.

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"bpgreen" post=250989 said:

Another thing to consider is that the BU:GU ratio is really just a starting point. Depending on your ingredients, the OG reading can be a little misleading. For example, if you've got a lot of steeping grains and/or you mashed at a higher temperature and/or used some nonfermentable sugar like lactose, you're going to end up with more sugar that didn't ferment, so there will be more residual sweetness. Conversely, if you mashed at a lower temperature and/or used a fair amount of adjuncts and/or used a yeast that attenuates aggressively, you'll end up with fewer unfermented sugars and more bitterness than the ratio would indicate.


Great point bpgreen. This is something I didn't consider when using BU:GU ratio. I understood how gravity could impact the perception of bitterness. And even though I know you can mash at a lower temperature to showcase the hops or a higher temperature to showcase the malt, I still took the bitterness to gravity ratio at face value.

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