Hop Isomerisation Temperatures

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I think this information is useful to know, because assuming that this graph is correct i might be able to approximate how to get 7 minutes worth by putting it in at a certain temperature somewhere in the cool down process, and maximize my ROI B)

3824d1199021766-better-hop-utilization-double-hop-ipa-hop_utilization.jpg


Sorry, you are assuming wrong. I'm amazed this graph is still being referred to. Send straight to the waste bin where it belongs.... :)


Cheers Ross
 
theory shmeory.

No chilled beers are measurably more bitter than beers which are not no-chilled. I know, I have in fact measured the difference. Enough measurements to be statistically significant for the fussy science types out there, iso octane extractions if you care.

I made graphs and tables and all that shit.... dont ask, they are all gone in the great hard drive crash of years past. However, I have retained the useful result.... the useful result being that if you take a recipe and you look at your hop additions - the difference that will be made by no-chilling the beer is the same as you would get if you made your last hop addition and at the time you were meant to turn off your kettle... you forgot and left it run for an extra 10-15 minutes (ignoring volume changes) - then chilled it. Fast with an immersion chiller.

That was all worked out using Pro-mash and the Rager ibu formula, which is what I use. Basically i just plugged in numbers till things worked out. So wort A ended up say 5% more bitter in the NC version vs the Chilled version, so i plug the recipe into pro-mash and click the boil time up till the IBUs have gone up by 5%. Repeat for all samples. Work out a range and call it as good a guess as any.

Turns out its 10-15 mins. If you happen to shove an amount of hop pellets (loose) into your actual cube and not boil them at all, that'll add bitterness as though you had boiled them for 20-30mins.

You want to "compensate" for no chill but use software that assumes you do chill? - calculate your bitterness as though you were going to make all your additions 10-15 minutes earlier in the boil (including your bittering charge) and then simply reduce the bittering charge till your expected IBUs match the recipe. DONT actually change when you add the hops. Not that hard really.

And sweeties.... thats just about as close as you are ever going to get. I used to chill with an immersion chiller and swapped to a plate chiller... all my hops sat in a kettle full of very hot wort for 20-30 minutes longer than they used to. would that have changed my bitterness?? Of course it would. Does the brewing software take it into account? Hell no, but you dont see ******* thread after thread on AHB about how people cant calculate their bitterness properly anymore because they bought a plate chiller.

How about the different IBU calculators that DO assume you chill? Try going into the settings of your software and changing from Rager to Tinseth, or Daniels, or "generic" and see what that does to the expected IBUs over a few different recipes. Or how about FWH?... my software defaults to FWH reducing IBU levels significantly vs a normal boil, other software defaults to it increasing IBU levels?? Oh - and how many of you take note of the date your hops were picked, then plug their proper age & the type of material they were stored in & the temperature they were stored at, into your software to estimate their degredation in IBU potential during storage. And what effect did the repackaging and storage conditions that happened at the HB shop before you even bought them have? Do you compensate for potential between hop flowers and hop pellets? - what about type 90 pellets vs Type 45 pellets and each of those vs flowers? What about different varieties of flowers whose cones have different physical structures which will affect the way that the hops resins are able to be physically dissolved in the boil? what about the vigor of your boil? What about the difference in utilisation potential between dark and light worts with different pH levels? hmmm? I could keep on going for a while too.....

What I'm kind of unsubtly trying to get accross, is that ALL the hop formulas are just a moderately educated guess - and none of them are very accurate at all (able to measure remember). They ALL require you to stick with them and not change your technique, over a few brews and feedback the way the beer tastes into your recipe development. Adding a 10-15min "No-Chill Factor" into the mix is barely even going to make a ripple in the lake of mixed bullshit and guesswork that makes up Homebrew IBU calculations.

Brew your beers the way the recipe says.... if you notice that your No-Chill beers (or all your beers if you only no-chill) are always a little more bitter than you'd like. Reduce the bitterness you add! Its that simple. If by chance you'd like a hint on how much to reduce it - well then, a good place to start is to calculate the bitterness in your no-chill beer, as though you'd boiled all your hops for 10-15min longer than you actually plan to. the increase in bitterness you get is how much you should reduce your bittering addition by.

See how it works out - tweak as required to suit your brewery - sorted.

TB


I like Thirsty's posts. Half our family members are doctors - research and MD and this type of reply is common around our family gatherings...
 
That graph is very useful for conveying to someone who has never boiled hops before, what happens in a nutshell - which I'm pretty sure was its intended purpose.

Somehow I don't think those lines are connected datum points.

Since the graph indicates that before you've even added your hops, your wort has already increased in bitterness by 15%, and is 10% more flavourful, we can be quite sure.

Use Kev's graph when cloning VB.
 
theory shmeory.

No chilled beers are measurably more bitter than beers which are not no-chilled. I know, I have in fact measured the difference. Enough measurements to be statistically significant for the fussy science types out there, iso octane extractions if you care.

I made graphs and tables and all that shit.... dont ask, they are all gone in the great hard drive crash of years past. However, I have retained the useful result.... the useful result being that if you take a recipe and you look at your hop additions - the difference that will be made by no-chilling the beer is the same as you would get if you made your last hop addition and at the time you were meant to turn off your kettle... you forgot and left it run for an extra 10-15 minutes (ignoring volume changes) - then chilled it. Fast with an immersion chiller.

That was all worked out using Pro-mash and the Rager ibu formula, which is what I use. Basically i just plugged in numbers till things worked out. So wort A ended up say 5% more bitter in the NC version vs the Chilled version, so i plug the recipe into pro-mash and click the boil time up till the IBUs have gone up by 5%. Repeat for all samples. Work out a range and call it as good a guess as any.

Turns out its 10-15 mins. If you happen to shove an amount of hop pellets (loose) into your actual cube and not boil them at all, that'll add bitterness as though you had boiled them for 20-30mins.

You want to "compensate" for no chill but use software that assumes you do chill? - calculate your bitterness as though you were going to make all your additions 10-15 minutes earlier in the boil (including your bittering charge) and then simply reduce the bittering charge till your expected IBUs match the recipe. DONT actually change when you add the hops. Not that hard really.

And sweeties.... thats just about as close as you are ever going to get. I used to chill with an immersion chiller and swapped to a plate chiller... all my hops sat in a kettle full of very hot wort for 20-30 minutes longer than they used to. would that have changed my bitterness?? Of course it would. Does the brewing software take it into account? Hell no, but you dont see ******* thread after thread on AHB about how people cant calculate their bitterness properly anymore because they bought a plate chiller.

How about the different IBU calculators that DO assume you chill? Try going into the settings of your software and changing from Rager to Tinseth, or Daniels, or "generic" and see what that does to the expected IBUs over a few different recipes. Or how about FWH?... my software defaults to FWH reducing IBU levels significantly vs a normal boil, other software defaults to it increasing IBU levels?? Oh - and how many of you take note of the date your hops were picked, then plug their proper age & the type of material they were stored in & the temperature they were stored at, into your software to estimate their degredation in IBU potential during storage. And what effect did the repackaging and storage conditions that happened at the HB shop before you even bought them have? Do you compensate for potential between hop flowers and hop pellets? - what about type 90 pellets vs Type 45 pellets and each of those vs flowers? What about different varieties of flowers whose cones have different physical structures which will affect the way that the hops resins are able to be physically dissolved in the boil? what about the vigor of your boil? What about the difference in utilisation potential between dark and light worts with different pH levels? hmmm? I could keep on going for a while too.....

What I'm kind of unsubtly trying to get accross, is that ALL the hop formulas are just a moderately educated guess - and none of them are very accurate at all (able to measure remember). They ALL require you to stick with them and not change your technique, over a few brews and feedback the way the beer tastes into your recipe development. Adding a 10-15min "No-Chill Factor" into the mix is barely even going to make a ripple in the lake of mixed bullshit and guesswork that makes up Homebrew IBU calculations.

Brew your beers the way the recipe says.... if you notice that your No-Chill beers (or all your beers if you only no-chill) are always a little more bitter than you'd like. Reduce the bitterness you add! Its that simple. If by chance you'd like a hint on how much to reduce it - well then, a good place to start is to calculate the bitterness in your no-chill beer, as though you'd boiled all your hops for 10-15min longer than you actually plan to. the increase in bitterness you get is how much you should reduce your bittering addition by.

See how it works out - tweak as required to suit your brewery - sorted.

TB


Excellent post. I switched to no chilling after a few years of chilling a few years ago. Lots of confusing info about adjusting calculations, so i just didn't adjust them at all. For me, the beers are fine, even no chilled 10 minute IIPA's. I think i've had one beer in all that time i felt was too bitter, but i FWH'd a shitload of galaxy and boiled for 90, rather than my ( at the time ) normal 60.
 
I was just trying to find useful and digestible information on this exact thing.

I have also heard from numerous sources that 80 is a good rule of thumb for basically no significant utilisation, though if it was 1/4 the rate of boilling as micblair says, I would still consider it significant.

I have heard that the method used in Thornbridge's Jaipur is to get the beer to 80C somehow (perhaps running back to kettle via HX) and do a late hop stand before chilling to maximise the oils and resins without converting the AAs. I once tried this at 60C because I figured it is still quite hot and the edge of pasteurisation, but I got diddly squat from my hops, I think it was the equivalent of a few hours of dry hopping.

And every brewery knows that you pick up a bunch of IBUs in the whirlpool, but if you know it and it is constant, you can easily adjust for it.
 
Excellent post. I switched to no chilling after a few years of chilling a few years ago. Lots of confusing info about adjusting calculations, so i just didn't adjust them at all. For me, the beers are fine, even no chilled 10 minute IIPA's. I think i've had one beer in all that time i felt was too bitter, but i FWH'd a shitload of galaxy and boiled for 90, rather than my ( at the time ) normal 60.
But you probably have a different idea of a given IBU based on taste and calculations rather than measurement.
 
Exactly, everyone has a different taste and perception of bitterness, so what works for brewer A, might not work for brewer B.

I also think that between home brewers, there is a much greater variable in our setups than we give credit for. 2 brewers using a 3v setup may achieve different results in regards to cooling ( cube ), boil intensity etc blah blah.
 
Sorry to raise a thread from the dead.... But I have a question that I think fits in here.

Why do we boil the wort...
If hop isomerations goes down by 50% every 10C at 99C it must be 95%+
DMS boils at 37.24C
Pasturisation occurs at 60C

It seems to me if we kept it at 99C/simmer we would use way less energy and need way less water (no boil off).
Is the boil just a way to stir the wort hence the "rolling boil"? and if it is couldn't we just mechanically stir it?

I am almost deffinitly missing something but I havent found it on google yet :)

JJJ
 
Hop utilisation, evaporation of various volatile compounds (pretty sure dms is only one of a few, need to check), colour development, achieving desired gravity, development of flavour compounds like melanoidens, wort sterilisation/pasteurisation.

Pasteurisation does not 'occur at 60'. Pasteurisation is a combination of time and temperature (and presumably other factors like pH) - the cooler temperatures require longer to be successful. Also not all microflora are destroyed at the same temperatures.

DMS may evaporate at that temp but it will evaporate more effectively at higher temps. Furthermore the precursor to DMS needs to be transformed into DMS by higher temperatures, otherwise it remains in the wort where it can be transformed by yeast or bacteria later. You are reducing SMM levels through transforming to DMS and boiling off.

Look up 'the function of wort boiling' and find the article that's linked to IBD. From hazy memory the author is Rourke or O'Rourke.
 
There was a retailer on here recently selling an under bench brewery. Can't recall the name of it, but hopefully someone can chip in with it. They did not do a full rolling boil due to limited heating, but they claimed a lot of big breweries did not either. There was a few threads started about the brewery.
 
Thans for the link Manticle,

It was interesting but nothing in it really said what the difference was between boiling (100C) and simmering say (99C). The only comparison I could see was on page three where they said for nitrogen removal (didn't even know we were trying :) ) it was based on agitation not boil off rate.

QLDkev do you have a link? It may not make allot of difference to a big brewery as it sounds as if they catch most of the heat in heat exchangers?

Does anyone have experience with the difference between, really boiling the shit out of it vs a very mild boil/simmer?

Thanks guys

James
 
The next update for beersmith is going to include temp for hops i email them. i will look when i get home and i post what was emailed to me
 
Perhaps this might be useful. This link is for Brewer's Friend website and at the top of the menus you see can see "New Beer Recipe" I have registered there and have saved many recipes and created them there. What is useful to this thread is when you get past the malt ingredients, your grain bill or extracts if you do not do all grain brewing, and the hop additions. There is a place for figuring time, and amounts, and shows how much IBU you are going to be getting by when you add the hops during the process and how much of what hops and it's alpha acid content. You pick a style you are doing and you can also see if it is falling withing the style and adjust accordingly.

I recently made up an Irish Stout using this recipe creator, using Stout Malt from Malting Company of Ireland, East Kent Golding hops, Roasted barley and yeast from Ireland, and adjusted the water to pretty much emulate Guinness water and this beer took 3rd place last month in the yearly American Home Brew competition. I say this, because it is a way to take a lot of guess work out of figuing in how much hops, etc you are needing to achieve what you are after in the end.

Link: https://www.brewersfriend.com/

In my process I use a pressure cooker for some of the wort and boil my hops in the pressure cooker for about 20 minutes. This is a higher temp, under pressure and can accomplish that which might take quite a bit of boiling time. I still boil to reduce DMS, but I add the pressure cooked wort and hops to the main pot after the pressure cooker boil period.
 

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