Hop Stands and IBU calculations

[philm00x]

I'm working a recipe on beersmith and I'm having some difficulty trying to work out how to go about figuring IBUs for it. I want to do a hop stand/aroma steep at the end of the boil and the latest version of the software has a function to utilize hops for aroma steep after flameout, which in turn calculates IBU contribution to the recipe. Per the calculation, it adds about 16 IBU, but then a flameout boil addition obviously adds 0 IBUs. I guess I just want to try and figure out how the addition will affect bitterness in the beer, as I really just want it to be for aroma (though some hop oils will be utilized, I'm sure).

[BlackDuck]

That's a good question....I never noticed that choosing "boil" for "0" minutes returns an IBU rating of 0. And choosing "Steep/Whirlpool" for a given amount of time does return a value for it's IBU contribution.

HHmmm....I wonder if Brad at BeerSmith can give you some idea of what's going on. If you email him, he's usually pretty good at returning emails.

[Beer-lord]

Try posting the question on the Beersmith forum. You don't always get quick answers like you do here but Brad does sometimes answer forum questions or email him directly.
It might already be answered there.

[braukasper]

Actually you will get IBU's when doing a flame-out addition. I am unsure what temp is the cut off.

[mashani]

From what I know, anything above 190 and you get about the same IBU extraction as in a boil. Some of the new fangled automatic AG machines never bring the wort to a boil, they just bring it up to around 190 and hold it there the entire time.

Other then that, it gets complicated, but you will get some IBU extraction even at much lower temperatures. Somewhere a long time ago either here or on Mr. Beer forum I posted a chart that shows the correlation - I can't find it now but I'll keep looking - but it's a non-linear formula that involves Time, Temperature, and PH - ALL of those things matter as far as what and how much get extracted from hops.

And this isn't just about IBUs, there are lots of other goodies in the hops. Temperature and PH also affects what of those get extracted, and also involves what gets flashed off into the air after extraction, which is why I hopstand with a lid on the pot, so flashed off volatile oils re-condense and fall back into the wort - same concept as perfume making distillation, the compounds are not destroyed, they just go up your nose instead of staying in the beer, unless you can re-condense them.

That also ties into the idea that boiling hops in wort is necessary to extract stuff from them is not correct. You do get stuff extracted. You just get it in different quantities/proportions. So you can't duplicate a recipe by boiling your hops in water, as the PH is totally different then wort. But you will get something. There is not any magical binding of hop compounds with wort compounds, that's made up nonsense. Isomerization is time/temperature/ph reaction, it's got nothing at all to do with wort beyond that.

This is also why I disagree with people who say putting late hops into your fermenter doesn't get you anything. It most certainly can. If you taste the hops you pull out of a 10 minute addition, they still have lots going on. Even at fermentation temperatures some hop oils will get extracted given enough time. Anyone who logically thinks dry hopping works, but putting hops that still have lingering flavor compounds in them in doesn't work is nuts.

That doesn't mean you WANT those flavors though. It depends on the hops, if you are sensitive to certain hop flavors (grassy what not) then leaving certain hops in might get you that. But for my own consumption, I tend to leave everything in that is after T-20 because I feel I get something more out of them, except for specific hops where I find doing so brings something I don't like to the party.

Anyways I'll try to find that chart, I think it came out of some $2,000 commercial brewing book. (I found it online somewhere).

[jimjohson]

I think I remember reading you'll get some bitterness from anything over 160f

[mashani]

Yes, you do. When I hop stand starting at 160 and letting temperature fall on its own for 20 or more minutes I count the hops as 10% utilized for AAUs in my guesstimate. I don't know if that's totally accurate and I don't really care - the long answer is complicated as mentioned above, but it seems to be close enough to work on a recipe and have it come out similar to what I expect based on the hops I'm using.

But then really we are getting into another nitpick of mine, which is just because the hop package says it's 12% AA, it doesn't mean it is. At one point it probably was... but the actual AAs (and other stuff) still in that package depend on hop variety, storage conditions, and age... so we simply do not know what our real AA contribution or other volatile oil contribution from the hops we use will really be unless we have access to a lab or unless we know the storage conditions for the entire life of the packaged hops and exactly when they were packaged. So IBUs we guess are just that... guesses. So there comes a point where worrying too much about it is just worrying for no reason. That's why I don't usually bother measuring hops lower then 1/4oz or 1/8oz for the big boys. Anything smaller is just getting into "does it really matter?" territory.

So my theory in general is just make beer.

[Gymrat]

Hop standing is such an inexact science that the only way you can really learn about it is to do it. I experimented with different times and dropping them in at different temperatures over several brews. I discovered I get my best results if I cool the wort to around 160 to 170, turn off the chiller, then drop the hops in and leave them for half an hour before turning the chiller back on. And my results vary due to ambient temperatures as I brew in my garage, and on a cold day 30 minutes will take that 160 down to 120, on a warm day it cools to 140. The rate at which it cools has a profound effect.

My point is, if you want to use hop standing in your recipes you really need to experiment with them for yourself. Brewing software is NOT going to tell you what you need to know. Only personal experience will.