Perceived bitterness vs. IBU's

I brew using a Brew Magic RIMS system. The malt flavor I can get is just awesome. My problem is that my perceived bitterness of my beers seems much less than the calculated IBU’s from my recipe. For example, I’m sipping on an Alt that I brewed using NB’s kit. I cut back in the hops from the recipe because the calculated IBU’s for the enclosed hops were out of range for the style. The finished beer is good- great Munich malt presence, but I’d like it more bitter. I kegged an ESB today. The recipe called for about 35 IBU’s, but I bumped it up to 50 and the beer at kegging had some nice bitterness, but not what I’d think 50 IBU’s would represent. Most of the helles I brew have great malt flavor, but lack the balancing bitterness.

I use RO water and build my brewing water using guidelines from Bru’nwater. So I don’t think my water or mash pH is an issue.

Any thoughts?

You don’t mention how you are calculating the bitterness…software and utilization formula? In addition, are these free hops or are they bagged in some way? Is the boil active enough?

It sounds like its either formulation or utilization that is not calibrated for your brewing.

I mirror the same questions Martin stated.
Two things I will interject.
#1 Even if things went really haywire in brewday or overall calcs 35-50 IBU is noticeable no matter the slight differences such as I will mention in my second question and you would still hover around at a low/ high of 40-60 IBU if you were shooting for 50 depending on circumstances. In a simple ESB you would know the difference between 20-40 and 40-60 because of the simple malt bill typically used. It could also be possible that your palette is desensitized to bitter. Have other “tasters”/ Friends etc… or judges mentioned this factor also?
I have used promash and Glen Tinseth’s Calculator to find agreement of usually 2-5 IBU. Such as an APA I made today. Tinseth’s actual calculator said it would be 36 IBU and promash was 38 IBU set to Tinseth. So I will expect around 37 or so. This is a mirror image of a beer I made 60 days ago and it was spot on at 38 IBU average found between the two.

#2 Depending on the age, storage capabilities of said hop and degradation over time become slight factors if using hops that are well over 6 months old. Just something to mention if it was not already a factor used in this application.

I don’t see anything from the previous posts that I would disagree with.

First two items I would check would be how your software is calculating IBUs (in most programs this is something you can set, and thus can get wildly different numbers for the same recipe), and the second would be hop freshness. I don’t typically adjust my bitterness calculations for hop freshness, though I probably should. The hops I buy are vacuum packed, but then stored at room temperature until they are sold. I keep them in the freezer, sometimes for a year or two before the package is finished. I know this has occasionally resulted in beers that should have more bitterness, but it’s never been bad enough to make me go to the extra effort. If however I knew the hops had been treated more poorly, I might reconsider.

Thanks fellas. Good points. I use Promash to get the IBU’s, so that part’s at least consistent. I usually use pellet hops that are vacuum sealed and kept in the freezer. And I usually get a good rolling boil for at least 60 min.

Maybe it is my palate to some degree. I think I’ll just bump up the IBU’s on the next few batches and see what happens.

Cheers.

The only thing I would add to what the other guys have said is in reference to the above statement. You may find that you perceive more bitterness after the beer is carbed. I kegged a couple IPA’s recently that I did not think were even close to the predicted bitterness when I racked to keg, but my perception changed after they were carbonated.

Maybe it’s your water.

Another point to consider is whether you actually know what 35, 15, or 55 IBU tastes like to you. In other words, have you calibrated yourself with beers with a measured IBU? I’m not sure how many good craft beers actually measure their IBUs rather than estimate it as we do. I imagine some of the larger ones do and you could compare your beers side-by-side with similar (stylistic) commercial examples. If you did this, then you’d be able to begin to know if its a utilization thing or a perception thing.

Have you played around with sulfate versus chloride concentrations in the finished beer?

Good point. Low sulfites will mute bitterness.

Most commercial breweries of any size measure bitterness as part of the QC process. Unfortunately, measured bitterness doesn’t always correlate to perceived bitterness unless your ingredients and process are fixed and you are just trying to detect variations. In other words, if you are trying to brew the same beer over and over again, a measured difference in bitterness will likely correlate to a perceived difference. But if you change your process or recipe significantly, that correlation could go out the window. Using FWH is the best example of this. By commonly used lab tests for bitterness, they impart the same or slightly higher IBUs than 60 minute hops, but they are not perceived to be as bitter. Changes in water chemistry can similarly affect perception which is again not caught in the lab tests.

I’m thinking along the lines of Denny and Shadetree. RO water that is short on sulfates will produce a beer where the hops do not come through as you might expect. I have always heard that soft(er) water will mute hops to the point that more are required to get the same bitterness. I have also heard that something like a Pilsner Urquell (made with very soft water) needs more hops than you might expect to get to the bitterness you experience. I would like to know your sulfate and chloride levels (in ppms) and go from there. I’m thinking that a bit more sulfate could make your hops pop.

Good point. Low sulfites will mute bitterness.[/quote]

No offense, but that’s low sulfates…different thing.

Good point. Low sulfites will mute bitterness.[/quote]

No offense, but that’s low sulfates…different thing.[/quote]
No offense taken; too much winemaking on the brain lately.

That would do it!

I think you guys are onto something…
Here’s my predicted ions from Bru’nwater:
Ca- 44
Na-8
SO4- 27
Cl- 77
HCO3- 16

Looks like a little more sulfate ion is probably in order.

[quote=“pkrone”]I think you guys are onto something…
Here’s my predicted ions from Bru’nwater:
Ca- 44
Na-8
SO4- 27
Cl- 77
HCO3- 16

Looks like a little more sulfate ion is probably in order.[/quote]
What target profile are you using in Bru’nWater?

For an ESB, you’d probably want to try Amber Balanced (or yellow balanced if the beer is lighter) to see if that results in the desired flavor. If that doesn’t yield the desired bitterness, give Amber Bitter a try.

[quote=“pkrone”]I think you guys are onto something…
Here’s my predicted ions from Bru’nwater:
Ca- 44
Na-8
SO4- 27
Cl- 77
HCO3- 16

Looks like a little more sulfate ion is probably in order.[/quote]

I’d shoot for 8x that sulfate figure.

[quote=“pkrone”]I think you guys are onto something…
Here’s my predicted ions from Bru’nwater:
Ca- 44
Na-8
SO4- 27
Cl- 77
HCO3- 16

Looks like a little more sulfate ion is probably in order.[/quote]
Bingo. Too much chloride without some balancing sulfate will give the beer a rounder, smoother character and mute hops a bit. You will have to decide how much sulfate to add based on your preferences and tastebuds but I guarantee that if you just bring the sulfate in line with the chlorides (about 3x) you will notice a big difference in how your hops are perceived. The higher you go, the crisper the hop profile should be.

Ah, that is very low sulfate. Sulfate is a desirable component in bittered beers to help dry the finish and allow the bittering perceptions to come through. A dry finish is one component that most good beers have. After judging thousands of homebrews, a dry finish is often an important deficiency that many homebrewers need to correct to improve drinkability.

I was guilty of mashing far too many beers at over 154F and had overly full finish and body. I now rarely exceed a mash temp of 154F and sometimes include a reduced temp step in the 146F range to improve fermentability. Along with those revisions to improve fermentability, the addition of sulfate in the brewing water is important in hoppy and bitter beers. In an ESB, I’d say that at least 100 ppm sulfate is a requirement. Boosting the sulfate level to a typical pale ale level of 300 ppm may be excessive in an ESB since there is a degree of bready, caramelly notes that might be lost with that higher sulfate level.