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BeerSmith Software => BeerSmith 2 Bugs/Support => Topic started by: slash2000 on November 26, 2013, 11:24:38 PM

Title: Steep/whirlpool should add bitterness to every addition
Post by: slash2000 on November 26, 2013, 11:24:38 PM
G'day all,

When I select the new steep/whirlpool option, it calculates the bitterness for the whirlpool addition pretty much spot on to what I've worked it out to be before, so I'm happy with that.

However, if you select the whirlpool option, it should be adding bitterness to every hop addition, not just the ones at flameout. Every addition in the kettle will continue to isomerise at the higher temperatures.

I think that this oversight might lead to a lot of people accidentally creating face-exploding bitterness bombs when experimenting with this technique!

Cheers.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: Oginme on November 27, 2013, 05:24:09 AM
While I can see it adding some bittering increase from the late hops, there would be very little gain from the early, bittering additions.  In reality it depends too much upon an individual's brewing process to really calculate out.  If one brewer chills immediately upon flame-out and then changes his process to allow for whirlpooling, I can see where some of the late hop additions would increase the bittering over his previous technique.

Overall, the main issue is that someone needs to do the research first and provide data upon which to build a model for calculating the increased IBU contributions from previous hop additions due to whirlpooling.  Once that has been done, then I think there would be reason to include it into the program.  It sounds like and interesting topic to pursue.  Anyone got the time and money to do some studies?
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: MaltLicker on November 27, 2013, 07:39:38 AM
Compared to actual boiling time, it would be relatively less.  I just changed a 14% AA% boil hop from 60 mins to 90 mins, and that only bumped IBUs from 11.7 to 12.6, or 0.9 IBUs, or 7.6%.   

If 30 mins additional rolling boil time adds only 7.6% more IBU, then simmering longer still at less than boiling, after at least 60 mins of boil time, would probably be less than 7%.   And even at 7%, that would increase IBUs by 2 to 5 in most under-100 IBU beers, so still within the 5-10 IBU threshold detectable by human palates. 

As the difference between 60 and 90 mins reveals, there seems to be a point of diminishing returns on hop AA% utilization.   And whatever might be extracted in whirlpool would not impact total bitterness too much. 
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: brewfun on November 27, 2013, 08:09:01 AM
However, if you select the whirlpool option, it should be adding bitterness to every hop addition, not just the ones at flameout. Every addition in the kettle will continue to isomerise at the higher temperatures.

slash2000, I can see where you could have a concern about over bittering, but actual lab results would show something different. All in all, every place you can add an IBU, there are half a dozen places to lose it.

Maltlicker has a good point. Recipes are an estimate.

Issues such as wort viscosity, proteins and vigor of the whirlpool have an effect on the actual isomerization moreso than just heat and time.

At 90 minutes, as many isomers are destroyed as are created. Same with hitting 100IBUs. With the latter, other flavors are created in the process.

 
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: AnthonyB on November 27, 2013, 11:20:33 AM
G'day all,

When I select the new steep/whirlpool option, it calculates the bitterness for the whirlpool addition pretty much spot on to what I've worked it out to be before, so I'm happy with that.

However, if you select the whirlpool option, it should be adding bitterness to every hop addition, not just the ones at flameout. Every addition in the kettle will continue to isomerise at the higher temperatures.

I think that this oversight might lead to a lot of people accidentally creating face-exploding bitterness bombs when experimenting with this technique!

Cheers.

Slash2000 is completely right here.  It may even make sense to just add this as an equipment setting to determine how long cooling usually takes place or an expected utilization after the boil as a setting.  It makes no sense to have a 5 minute hop addition extract fewer IBUs than a flame out addition.

I use BeerSmith for professional brewing and I was forced to designate 5 minute additions as 20 minute additions and flame out additions as 15 minute additions to get the IBUs to come out even in the same ball park as I saw for finished fermented beers that I had measured.  I was really looking forward to this update, but this oversight has made it useless.  I will be forced to continue to fudge the numbers, which is really a shame.

-Anthony
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: BeerSmith on November 27, 2013, 06:20:56 PM
Hi,
  I faced several challenges here:
  - There is minimal research available on what whirlpool utilization really is!  The best articles I could find were centered around 90C and indicated about 50% of boil utility for whirlpool/steep additions.  This is what I added to the software.  However the real scientific literature here is very thin.

  - When we talk about leftover boil hops it is not simple to calculate their whirlpool effect since - many of these hops have already been "spent" in the boil, and have limited alpha acid still to give up and also these hops often fall out as trub during whirlpool/steeping limiting their contributions.  I thought about trying to make a really complex equation to handle this but decided instead not to do it, at least for this first round.

  Considering the "old" version considered ALL whirlpool/steep additions to provide zero IBUs, and also did not add any contribution from boil hops during the steep/whirlpool phase, I think this is at least a step in the right direction. 

Obviously it is not perfect, and I'm hoping brewers will begin to develop a better body of knowledge around the exact values here so I can develop it further.

Cheers,
Brad
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: slash2000 on November 27, 2013, 07:13:13 PM
Thanks for your reply Brad.

If it helps, the new Beersmith feature calculates almost exactly what I manually calculate whirlpool IBU's should be in my recipes, so it must be very close to the mark.

In terms of hops being "spent" before the whirlpool, I imagine this is true, but the main problem comes with late additions (at or after the 20 minute mark, typically the flavour/aroma window).

Typically I find a whirlpool/steep adds bitterness equivalent to ~10-15 minutes boil (I usually add 12 minutes). Some examples of the problem I'm talking about:

50 grams of 10% AA hops in 1.050 wort:

20 minute boil = ~40 IBU + whirlpool = ~53 IBU (33% increase)

10 minute boil = ~24 IBU + whirlpool = ~43 IBU (79% increase)

5 minute boil = ~13 IBU + whirlpool = ~36 IBU (280% increase!)

It's not so much a problem with 60+ minute additions where the difference is virtually zero, but if I was making a "hop burst" beer (all/most hops under 20 minutes) the difference in the end result would be massive.

I appreciate that whirlpool/steep additions have limited known science at this stage, but it's something I felt should be brought to your attention.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: grathan on November 28, 2013, 07:25:52 AM
I've always thought people whirlpool at lower temperatures to avoid isomerzation altogether while still getting the flavor from the hops.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: tom_hampton on November 30, 2013, 02:49:44 PM

Slash2000 is completely right here.  It may even make sense to just add this as an equipment setting to determine how long cooling usually takes place or an expected utilization after the boil as a setting.  It makes no sense to have a 5 minute hop addition extract fewer IBUs than a flame out addition.

I use BeerSmith for professional brewing and I was forced to designate 5 minute additions as 20 minute additions and flame out additions as 15 minute additions to get the IBUs to come out even in the same ball park as I saw for finished fermented beers that I had measured.  I was really looking forward to this update, but this oversight has made it useless.  I will be forced to continue to fudge the numbers, which is really a shame.

-Anthony

Anthony, I agree its not really fully baked, but its not quite "completely" useless.  It actually gives you a way to slightly more accurately calculate your bitterness, and represent the actual process you follow.  Here's how:

1.  Place all BOIL additions at their appropriate times (90, 60, 30, 15, 10, 5, 0, etc).  Let BS2.2 calculate the IBU contributions. 

2.  Place all whirlpool additions at their appropriate times.  Let BS2.2 calculate the IBU contributions.

3.  Add additional whirlpool hops for your late boil hops, with a whirlpool duration that equals your total whirlpool time.  You could create separate hop ingredients with a name that indicates that these are "fake" and should not actually be added to the whirlpool.  Eg:

"whirlpool Centenniel (do not add)"  or  "(skip) Centenniel"

This would allow you to accurately represent your Boil additions on your brewsheet.  Second, this would allow you to take advantage of the BS2.2 "whirlpool" formula.  You can fine tune the above by adjusting the "whirlpool time" of your fake additions if your results demonstrate that is necessary. 

Obviously, its still fudging the numbers...but, it does seem like a step in the right direction.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: tom_hampton on November 30, 2013, 03:04:10 PM
Hi,
  I faced several challenges here:
  - There is minimal research available on what whirlpool utilization really is!  The best articles I could find were centered around 90C and indicated about 50% of boil utility for whirlpool/steep additions.  This is what I added to the software.  However the real scientific literature here is very thin.

  - When we talk about leftover boil hops it is not simple to calculate their whirlpool effect since - many of these hops have already been "spent" in the boil, and have limited alpha acid still to give up and also these hops often fall out as trub during whirlpool/steeping limiting their contributions.  I thought about trying to make a really complex equation to handle this but decided instead not to do it, at least for this first round.

  Considering the "old" version considered ALL whirlpool/steep additions to provide zero IBUs, and also did not add any contribution from boil hops during the steep/whirlpool phase, I think this is at least a step in the right direction. 

Obviously it is not perfect, and I'm hoping brewers will begin to develop a better body of knowledge around the exact values here so I can develop it further.

Cheers,
Brad


Brad-

Based on your formula, its seems that a first order approximation would be to calculate IBU contribution from the boil hops by extending the total duration of those hops by the length of the whirlpool and only adding 50% of that delta from the contribution at flameout. 

Anthony seems to be on the right track, a whirlpool is definatly an equipment profile thing.  The equipment profile is where we define our "hot side process".  So, it seems to make the most sense to include the whirlpool length as an option in the equipment profile.  This would then make it easier to calculate the additional IBUs for each hop addition (boil and whirlpool). 

An additional consideration might be whether the whirlpool is stirred or circulated during the steeping time.  Homebrewers have options that professional brewers may not have. 

EG, I don't whirlpool hot wort, its simply a steeping step to simulate a professional process.  I have an electric stirrer.  At the end of the steep, I use my immersion chiller and stirrer to chill the wort.  Then I whirlpool the chilled wort.  However, I could use my stirrer during the steeping process.  This might increase the isomerization process and more closely replicate a "boil" profile at a lower temperature (eg, like boiling at altitude). 



Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: grathan on November 30, 2013, 04:41:40 PM
Sounds pretty straightforward...


It should also be pretty easy to implement a "temperature option" for the whirlpool as well, since the dropoff of isomerzation is relatively linear with temperature. I propose %50 reduction in isomerzation for each 10 degree drop in degrees Celsius.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: brewfun on November 30, 2013, 06:32:38 PM
This topic was presented at the ASBC, last year. None of that information matches the conjecture, here.

Most of what you guys are talking about is ONLY relevant to beers with less than 70 IBU before whirlpool. I seem to be seeing a belief in unlimited upward accumulation of IBUs.... It just ain't so...

A German Brewing Chemist showed how a brewery can add up to 35% more utilization with time, temperature and process; then showed how those same variables can be applied to fermentation, filtration and packaging to reduce IBU persistence by 85%.

Another chemist showed extraordinary variation in IBU outcomes from identical worts based on changes in pH, Malt composition, protein content, kettle geometry, heat source and oxygen.

There is a MAJOR difference between calculations and what ends up in the finished beer. In other words, it's a lot easier to lose IBUs than to gain them.

Here's the thing: The bigger breweries figure 100% utilization on all hop additions. They then factor for process and fermentation loss and often have a net IBU packaging range that can be up to 15 IBUs wide.

Why? Because there just isn't that much difference in perceived bitterness of 65 to 80 IBU. Hop perception is a ratio of sweetness to bitterness that is amplified by our perception of hop flavor and aroma.

The magic of massive late hop additions isn't bitterness, it's the sheer saturation and enhancements to hop flavor that's really going on. Yeast absorb isomers, but also have enzymes to change hop acids into flavor compounds. ...And we don't know how to calculate that, either....
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: tom_hampton on November 30, 2013, 10:42:59 PM
Brewfun-

I can't speak for anyone else here, but I'm under no delusions of the unlimited upward accumulation of bitterness. 

The standard PtE recipe on the net has a calculated bitterness of 200+ IBU.  Even RR using pellets and extracts on a commercial system only manages somewhere shy of 100 IBU measured.  Given the generally lower utilizations of homebrew setups getting more than 65 IBU is unlikely regardless of process. 

So, any calculation by BS2.2 for a homebrewer that is greater than 65 is highly suspect and more than likely unattainable.  Anything north of 100 IBU is probably unattainable by anyone except using some very unusual (and probably laboratory based) process. 

That's not the point, though.  To take your position to the extreme, there is no point in calculating it at all, because so many factors can affect the final result.  The point is that you control those parts of the process that remove IBU and hop flavors from the wort/beer so that they are approximately constant. 

The calculation still has value.  It is still a numerical representation of the RELATIVE amount of bitterness that is likely to end up in my finished beer...provided that I control those process variables that will cause VARIATION in the amount of bitterness removed.   There are beers below 65 IBU.  Some people even brew beers with less than 30 IBU, GASP!   ;)

Take an extreme example:  a hop-burst'ed 30 IBU pale ale. 

Hop-Burst'ed (did I just make a word?  probably not, someone on HBD probably already did).

Now, what does my hop profile for this beer look like?  Lets say it is a single 5 minute addition of Centennial for a total of 20 IBU.  Following Brad's model above (I can't speak to its accuracy, but its a start), if I take half of the gain for a 35 minute boil (85 - 20 = 65 / 2 = 33 IBU), then I'm at 53 IBU, simply by steeping the wort for 30 minutes before cooling.  Do I really gain that much?  Probably not.  As you approach saturation, you will expect the rate to decrease.  Do I expect to gain NONE?  Uh...no, I don't think anyone would argue that.  So, its somewhere between 20 and 53 IBU.  I'd argue its closer to 53 than it is to 20.  But, that's just an opinion.  The actual results probably vary considerably based on kettle geometry alone, and flow mechanics alone. 

However, if I have a formula that gives me a consistent calculation, then I can adjust my recipe from batch to batch to compensate for my hop perceptions.  I can adjust the time or the amount, and get a scaled number that gives me a ballpark to shoot for.  Say, the above beer comes out "twice" as bitter as I wanted.  So, I adjust my time to give me 26 IBU.  Using, Brad's whirlpool formula, I should steep that same amount of hops (3.6 oz) for the last 15 minutes of the whirlpool.   That would give me 25.4 IBU according to the math. 

So, I try that...and again make an adjustment based on my perception of the result and the math.  Maybe now, I think that its not quite bitter enough.  So, I adjust the steeping time up to give me 5 more IBUs (calculated). 

Again, if I control everything else the same (pitching rate, yeast selection, fermentation temperature, fining method and duration, etc) then I should end up with a predictable change in bitterness.  If I change any of these other process parameters...then I may have to adjust up or down.  But, I have a good numerical parameter with some reasonable scientific basis to use as a foundation for my adjustment.   




Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: brewfun on December 01, 2013, 04:29:47 AM
I can't speak for anyone else here, but I'm under no delusions of the unlimited upward accumulation of bitterness.

Hi Tom! And welcome back!

I knew I took a chance in drawing you out with that post. I agree, you're not one to whom I was speaking. Neither was Brad, nor the idea of calculating whirlpool bitterness. I have no doubts about your abilities. You're one of the most advanced brewers I've come across in forums without actually meeting in person. Plus, you race cars and I'm a NASCAR fan.

That's not the point, though.  To take your position to the extreme, there is no point in calculating it at all, because so many factors can affect the final result.  The point is that you control those parts of the process that remove IBU and hop flavors from the wort/beer so that they are approximately constant.

Indeed, taken to the extreme, that could be one of my points. My actual point was NOT to take it to an extreme in either direction because of the variations between setups. My point is that IBU calculations are useful as a relative metric. 

In other words, once the beer is brewed and tasted the brewer can review the recipe and say "oh, that's what XX IBU tastes like." and with time, modify that perception to include various hop types, cohumulone levels and all the rest of the variables. Thus, as process and equipment improves, so will hop utilization and the brewer can calculate the adjustment.

Take that further, a brewer can read someone else's recipe and come up with something very similar, through a combination the recipe specs and understanding their setup.

These are the things that make a formula and recipe software valuable. Which is exactly the point I think you're making. Correct?

I work as a pro brewer. I brew in a pub and consult for startups. Before I posted, I did a reality check of both literature available to me and polled a few other brewers, ranging from 5000 to 140,000 bbl in size.

Whirlpool hop accuracy has only become a concern because it's now fashionable to add hops there. Plus the burst hop method to enhance aroma from a hop charge. None of this really existed as a concern or technique before the hop shortages began. When PtE was developed, there were no hops that cost more than $5/lb. Now, it's closer to $15 on the wholesale end. So, there is much more concern about maximizing return from a much more expensive ingredient.

My other point is that since this technique and its results are relatively new, there's scant data out there to show correlation between techniques and results.

The calculation still has value. 

100% Agreed! The current calculation that Brad is using has allowed me to dial my hop utilization back from 120% to 100% based on my most bitter beers.

There are beers below 65 IBU.  Some people even brew beers with less than 30 IBU, GASP!   ;)

Indeed! And these were the norm long before the burst/whirlpool hopped palate busters of today. The previous IBU calculation model served those beers very well. Hence, why I'm pointing out that once saturated, the IBU number isn't all that important.

I have core products that range from 14 to 88 lab measured IBUs. My top seller is a 26 IBU Export Pilsner and my third is a 34 IBU Red Ale. Second place is, of course, IPA at about 70 IBU.

My process is:
75 minutes kettle fill
15 minute rise to boil/hot break
90 minute full boil
20 to 45 minute whirlpool
(longer WP times for IPA/DIPA because it enhances hop flavor)
30 minute stand/settle (gravity, it only works so fast)
40 minute chill (valves wide open, this is the flow rate of the Hx)

A FWH then is in there for up to 5 hrs. Yet, what I get is flavor, not increased bitterness.

The Pilsner has an aroma charge at flameout which, according to the OP, should contribute more than 20 IBUs to the beer. It doesn't. It contributes the expected 2 IBUs even though it had 90 minutes of contact time at or above 195F.

The red follows a classic, all kettle addition hop schedule of an American Pale Ale. Even with the extended time post boil, it nails 34 to 35 IBU.

I was taught that only fully isomerized alpha acids persist in a beer. I was taught that it takes at least 45 minutes of boil to get strong persistence and that it is the boil agitation that does the trick, along with heat. Given that sweet wort is often surprisingly bitter but the bitterness fades with fermentation, that lesson has served me well.

My American Wheat's bitterness comes from a burst hop addition at 10 minutes of 14% aa Sorachi Ace. Twelve days into fermentation and it's pretty bitter at 20 IBUs. But, by packaging it mellows to 14, which correlates to the expected isomerization. In return, I get a pleasant light lemon aroma and a beer that tastes like a Japanese lager, rather than a flabby American wheat.

So, I try that...and again make an adjustment based on my perception of the result and the math.  Maybe now, I think that its not quite bitter enough.  So, I adjust the steeping time up to give me 5 more IBUs (calculated).

Exactly! If you think it needs a change, you do it. That's what being a brewer is all about! Quantifying it with a formula is a relative metric, not an absolute.

I'm certain that if you had the added data of ACTUAL IBUs, you'd hone that even more. Ironically, you could likely find that the IBU number doesn't change much, but the perception of aroma and flavor does. There's taste panel data from breweries that show bitterness perception is lower when hop flavor/aroma is lower. I think this taste panel data has shown up in AHA conference presentations.

Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: MaltLicker on December 01, 2013, 08:13:51 AM
Part of this discussion reveals the inherent differences b/t homebrewers and commercial brewers.  Brewers-for-profit required repeatability and "known outcomes" far more than homebrewers.   The worst thing that could happen to a homebrewer pushing the envelope is a wasted batch and around $50. 

And homebrewers need to accept that the tools and formulas that are being "baked into" software packages are very much "beta versions" themselves.   Rager's hop model was it for many years, and then Tinseth came along.   And how many people have duplicated Tinseth's results in a lab with any degree of precision? 

All these tools do is provide "best guesses" and then you have to actually taste the beer(s) and develop your own reference point for what a Tinseth 60 IBU beer with 1.060 OG tastes like.    That's a BU:GU ratio of 1.00, and your first data point from your brew system, which may or may not taste like the same beer off my system. 

Unless we send every beer to the lab and get the actual IBU calculated, I think we're playing with art more than science. 
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: tom_hampton on December 01, 2013, 11:13:24 AM
Hi Tom! And welcome back!

I knew I took a chance in drawing you out with that post. I agree, you're not one to whom I was speaking. Neither was Brad, nor the idea of calculating whirlpool bitterness. I have no doubts about your abilities. You're one of the most advanced brewers I've come across in forums without actually meeting in person. Plus, you race cars and I'm a NASCAR fan.

Thanks.  To digress for a moment: The reason I haven't posted in a while is that there is some issue between Simple Machines Forum software and Android OS.  I get an Error 303 almost every time I try and post from my Android device.  I use that almost exclusively for 'net browsing, for the obvious reasons of convenience.  This weekend I've been confined to the bedroom where my main computer is (a nasty head cold combined with Strep throat).  Hence, posting at will.  Anyway, back to the topic at hand.....

Take that further, a brewer can read someone else's recipe and come up with something very similar, through a combination the recipe specs and understanding their setup.

These are the things that make a formula and recipe software valuable. Which is exactly the point I think you're making. Correct?

Yes, absolutely.  I knew you weren't really intending the extreme position. Since you know JamilZ, you will possibly recognize my approach and position on such formulas (particularly hop formulas) as similar to his.  Quite frankly, many of my own thoughts on the matter come from listening to all of his TBN episodes.  I've also been a control systems engineer, and the algorithm described is essentially how a closed-loop control system works.  I don't need a perfect representation of real life, I just need a consistent prediction mechanism and feedback mechanism.  From those two things I can assess and adjust without regard for the lab results. 

My other point is that since this technique and its results are relatively new, there's scant data out there to show correlation between techniques and results.

100% Agreed! The current calculation that Brad is using has allowed me to dial my hop utilization back from 120% to 100% based on my most bitter beers.

Understood.  Of course, there are many more recipes and homebrewers out there now which/who are experimenting with whirlpool hops.  So, the need to have some method for representing/predicting the results, in order to drive repeatability and a common language between brewers.   

Indeed! And these were the norm long before the burst/whirlpool hopped palate busters of today. The previous IBU calculation model served those beers very well. Hence, why I'm pointing out that once saturated, the IBU number isn't all that important.

I distinguish between hoppy and bitter beers.  To me the flavors are very different---I'm sure they are to you, as well.  I get where people are coming from when they say that hoppy increases the perception of bitterness, but I have a strong preference for hoppy versus bitter.  A true 65 IBU beer with little or no late additions is not one of my favorite styles.  I much prefer the 2 lb/barrel 5 minute addition type of beers---IF I'm going to make a IPA/DIPA style. 

In actuality, I'm over the DIPA and related beer phase.  I still make a PtE variant a few times a year, simply due to demand (at parties and what not), but personally...once a year would be enough for me.  But, there are a few NorCal transplants here in TX...and they get a PtE craving every now and again...they seem to think mine is indistinguishable in their minds. 

However, it might be a curious experiment to move all the early PtE hops to the last 30 minutes of the boil. 

I have core products that range from 14 to 88 lab measured IBUs. My top seller is a 26 IBU Export Pilsner and my third is a 34 IBU Red Ale. Second place is, of course, IPA at about 70 IBU.

A FWH then is in there for up to 5 hrs. Yet, what I get is flavor, not increased bitterness.

The Pilsner has an aroma charge at flameout which, according to the OP, should contribute more than 20 IBUs to the beer. It doesn't. It contributes the expected 2 IBUs even though it had 90 minutes of contact time at or above 195F.

This is interesting, and says that the formula currently presented may not be valid.  You don't need a perfect formula, but you do need something that is in the ballpark.  An order of magnitude of error is NOT in the ballpark. 

I was taught that only fully isomerized alpha acids persist in a beer. I was taught that it takes at least 45 minutes of boil to get strong persistence and that it is the boil agitation that does the trick, along with heat. Given that sweet wort is often surprisingly bitter but the bitterness fades with fermentation, that lesson has served me well.

My American Wheat's bitterness comes from a burst hop addition at 10 minutes of 14% aa Sorachi Ace. Twelve days into fermentation and it's pretty bitter at 20 IBUs. But, by packaging it mellows to 14, which correlates to the expected isomerization. In return, I get a pleasant light lemon aroma and a beer that tastes like a Japanese lager, rather than a flabby American wheat.

Hmmm....interesting.  I have three questions:

1.  Is this decrease 6/20 = 30% consistent with other styles?  Higher?  Lower? 
2.  So, is it your opinion that the decrease from 20 to 14 is some function of the "full isomerization" you describe above (or rather the lack therefore due to the very late addition)? 
3.  What yeast do you use for your A.Wheat (cal-ale, or some less flocculant strain)?  I find that lesser flocculant strains pull more bitterness out of a beer after clarifying.  But, there is also an element of time (it takes a lot longer to clarify a crystal-hefe than a english IPA).  I haven't tried to control for this variable. 

Exactly! If you think it needs a change, you do it. That's what being a brewer is all about! Quantifying it with a formula is a relative metric, not an absolute.

The bold was also precisely my point.  I just need a way to take my "twice as bitter" or "twice as hoppy" taste perception and turn that into a recipe change that will be a better approx. of my goal.  As long as I get closer each time, eventually I'll get there.  Obviously, the better the formula represents real-life the less iterations it will take.  But, even a consistent but inaccurate formula will allow me to get there. 

Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: brewfun on December 01, 2013, 01:02:17 PM
Since you know JamilZ, you will possibly recognize my approach and position on such formulas (particularly hop formulas) as similar to his.

Heh. Jamil and I go back to some of his first wins at the CA State Fair. We were practically neighbors when I lived in N. Cal. He's always honing his observations and mining the trades for new data. I've nearly always been on the judging side of homebrew comps. Jamil has a lot of my score sheets in his files and I have a lot of his beers on my waistline.

This is interesting, and says that the formula currently presented may not be valid.  You don't need a perfect formula, but you do need something that is in the ballpark.  An order of magnitude of error is NOT in the ballpark. 

Right. The OP is correct IF the measurement is immediately post chill. The most IBUs will be found there. But, we all evaluate the beer in a glass, when it's done and say, "That tastes like XX IBUs." What persists are whole isomers (cis-isomers) and some trans isomers (I should probably look them up, but there are like five forms of alpha acids between the hop plant and a full stable isomer). Trans isomers fade and are generally less than 30% of the IBUs found in finished beer. This is a primer: http://mv.picse.net/fermentation/hops/how-are-the-alpha-acids-isomerised/

3.  What yeast do you use for your A.Wheat (cal-ale, or some less flocculant strain)?


It's my lager yeast, HP 925, a high pressure German strain. This gives me a place to park it and sort of regenerate it because of the lovely nutrients and proteins of wheat. I try to get 20+ batches out of a single purchase (that's about 12 to 14 generations).

I find that lesser flocculant strains pull more bitterness out of a beer after clarifying.  But, there is also an element of time (it takes a lot longer to clarify a crystal-hefe than a english IPA).  I haven't tried to control for this variable.

I'd concur. Yeast absorb isomers. Some strains more than others. Yeast also have enzymes to break isomers (remember that isomers are mildly antiseptic; yeast would rather not have a lot of them). The result of that breakage is a transformation of hop flavor, to us.

As a judge, yeast in suspension blocks my perception of hops and other flavors. It essentially can pull the curtains closed, giving a chalky, muddy flavor.

1.  Is this decrease 6/20 = 30% consistent with other styles?  Higher?  Lower? 
2.  So, is it your opinion that the decrease from 20 to 14 is some function of the "full isomerization" you describe above (or rather the lack therefore due to the very late addition)? 

It's only indirectly consistent. It's quite consistent with recipes that calculate out to 100+ IBUs. It is not consistent with my Pilsner, which is pretty stable through the whole process.

With the wheat, I consider it an artifact that there is not enough boil time to make more cis-isomers. In fact, the bitterness has a pithy, harsh quality until it fades. With the Pilsner, I believe that the process creates a lot more stable isomerization.

*phew!* I need a beer! Can I get you anything, while I'm up?  :D

PS: I was hanging out with a group of pro brewers (would that be a Mash of Brewers?) and the subject of Pilsner came up. There is a lot of respect for making a great Pilsner; if for no other reason that the instant you say it, we all know the recipe: Pilsner Malt, Noble Hops and Lager Yeast. Then, there's nothing to hide behind, so it's all brewer skill that separates good from great. Hop handling turned out to be as big a concern as tank space.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: tom_hampton on December 01, 2013, 01:39:19 PM

This is interesting, and says that the formula currently presented may not be valid.  You don't need a perfect formula, but you do need something that is in the ballpark.  An order of magnitude of error is NOT in the ballpark. 

Right. The OP is correct IF the measurement is immediately post chill. The most IBUs will be found there. But, we all evaluate the beer in a glass, when it's done and say, "That tastes like XX IBUs." What persists are whole isomers (cis-isomers) and some trans isomers (I should probably look them up, but there are like five forms of alpha acids between the hop plant and a full stable isomer). Trans isomers fade and are generally less than 30% of the IBUs found in finished beer. This is a primer: http://mv.picse.net/fermentation/hops/how-are-the-alpha-acids-isomerised/

That reference is maddeningly barely informative.  Now i have to learn where the trans-isomers go.  Do they precipitate out, or are they chemically unstable and break down into something else?  Do they react with something else when they do?  Does this reaction result in "other" flavors? 

Great another rabbit hole to dive into.  :-)

PS: I was hanging out with a group of pro brewers (would that be a Mash of Brewers?) and the subject of Pilsner came up. There is a lot of respect for making a great Pilsner; if for no other reason that the instant you say it, we all know the recipe: Pilsner Malt, Noble Hops and Lager Yeast. Then, there's nothing to hide behind, so it's all brewer skill that separates good from great. Hop handling turned out to be as big a concern as tank space.

A.  I don't make lagers.  My fermentation room is temp controlled at 9C.  That's on the harry edge of being able to properly ferment a lager, and I don't have a cold storage room/fridge for the actual lagering step.   Yes its a room, with space for 4 temp controlled primary fermenters, 4 aging kegs and 4 kegs on tap.  I can squeeze in another 4 kegs or two secondaries if needed (it has happened). 

B.  I'm not a big fan of the pilsner style or really lagers in general.  I can "appreciate" them, but my personal preference has always leaned toward ale yeast character.  That said, I think the Ale equivalent would be a Kolsch, and I'm a HUGE fan of these for much the same reason.  There IS something about the simplicity of a Kolsch, as with Pils.  I love the soft round flavor from the Kolsch yeast. 

I started with JZ's recipe which includes about 4.8% Vienna.  I'm currently playing with the amount of vienna (considering 5% to be an upper bound, and exploring the spectrum between 0 and 5%).

I suppose this bit is a little off the topic, though...as whirlpool hops and Pilsner/Kolsch have nothing to do with each other. 
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: AnthonyB on December 05, 2013, 06:21:36 AM
I'm certain that if you had the added data of ACTUAL IBUs, you'd hone that even more. Ironically, you could likely find that the IBU number doesn't change much, but the perception of aroma and flavor does. There's taste panel data from breweries that show bitterness perception is lower when hop flavor/aroma is lower. I think this taste panel data has shown up in AHA conference presentations.

I'm basing my complaints on actual measured IBU data from HopUnion's Alpha Analysis lab.  For our American Pale Ale I'm getting most of our IBUs from what are essentially whirlpool additions.  I have the beersmith utilization setting at 120%.  We do two 1100 liter batches into the fermenter.  OG is about 1.050 and Ferment with S-05.  For each half batch we add about 300g of 16% alpha hops at the beginning of the boil.  We then add 750g of 10.6% Alpha hops 5 mins before flame out and 750g of 10.6% Alpha hops after turning out the coils on the kettle.  The wort is stirred for 5 mins.  It settles for another 15 mins.  Cooling takes somewhere between 50 and 90 minutes per half batch depending on my water temps.  I've had this beer measured at 44 IBU and 38 IBU a few months after bottle refermentation was complete.

Before the measurements, I assumed that the 5 minute addition was roughly equivalent to a 15 minute addition and the flame out addition was equivalent to a 10 minute addition.  I think that the reality is closer to the 5 minute addition being a 20 or 25 minute and the flame out being a 15-20 minute addition based on my measurements.

I'd really like to be able to specify that all my hops will undergo a steep of some period of time which more or less matches up with my realized utilization so I can anticipate how hop changes or new recipes come out.  (I realized that the 60 minute addition isn't going to add anything more to the IBUS.)  As I mentioned before, with the current setup I'm forced to mark my late additions as being earlier in the boil in order to make the calculations reflect reality.  It's a shame to have to fudge a work around like this when dealing with the software.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: Beezer94 on December 05, 2013, 10:41:19 AM
It seems the easiest solution would just be to add a hot steep timer next to where the boil time is.  If I have a 60 minute boil and then I put in 30 minute hot steep, have it just add 15 minutes to all hop addition bitterness calculations.  So a 60 minute addition will be calculated for 75 minutes, a 15 minute addition for 30, and a 0(flameout) for 15 mins.

The formula you already use for hop additions shows how a 60 minute moved to 75 adds a tiny increase in IBU's so I think this doesn't need to be that complicated.  Unless we send out our personal hops for AA testing and have our beers sent to labs for IBU testing, it's always going to be an approximate expected value.

This is how I've manually adjusted for my hop additions for quite a while.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: brewfun on December 06, 2013, 08:49:08 AM
Before the measurements, I assumed that the 5 minute addition was roughly equivalent to a 15 minute addition and the flame out addition was equivalent to a 10 minute addition.  I think that the reality is closer to the 5 minute addition being a 20 or 25 minute and the flame out being a 15-20 minute addition based on my measurements.

This is a great bit of data. The use of actual measurements over assumptions is the only way to create accuracy.

Do you find that the numbers track similarly when the estimates and measurements are over 60 IBU?
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: AnthonyB on December 07, 2013, 05:32:28 AM
Before the measurements, I assumed that the 5 minute addition was roughly equivalent to a 15 minute addition and the flame out addition was equivalent to a 10 minute addition.  I think that the reality is closer to the 5 minute addition being a 20 or 25 minute and the flame out being a 15-20 minute addition based on my measurements.

This is a great bit of data. The use of actual measurements over assumptions is the only way to create accuracy.

Do you find that the numbers track similarly when the estimates and measurements are over 60 IBU?

I'll try to get some more data and post it when possible, but my feeling is that you really need to boost the amount of Alpha when you try to get over 60 IBU.
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: brewfun on December 07, 2013, 05:55:32 AM
I'll try to get some more data and post it when possible, but my feeling is that you really need to boost the amount of Alpha when you try to get over 60 IBU.

That matches what most breweries report. It's also in line with some recent ASBC papers, though they're focused on high gravity brewing for mass lagers (20+ Plato). 
Title: Re: Steep/whirlpool should add bitterness to every addition
Post by: natebriscoe on January 11, 2014, 08:49:45 AM
It seems the easiest solution would just be to add a hot steep timer next to where the boil time is.  If I have a 60 minute boil and then I put in 30 minute hot steep, have it just add 15 minutes to all hop addition bitterness calculations.  So a 60 minute addition will be calculated for 75 minutes, a 15 minute addition for 30, and a 0(flameout) for 15 mins.

The formula you already use for hop additions shows how a 60 minute moved to 75 adds a tiny increase in IBU's so I think this doesn't need to be that complicated.  Unless we send out our personal hops for AA testing and have our beers sent to labs for IBU testing, it's always going to be an approximate expected value.

This is how I've manually adjusted for my hop additions for quite a while.
I had thought of this myself. A boil\ steep\ knockout timer would be pretty handy, just due to some people chilling in 5 min some may take 2 hours.