Hop Time Roles

[hamstringsally]

recently did a brew of little creatures pale ale and was wondering what the role was of adding certain hops at certain times of the boil?
for this recipe over a 60 min boil

at the start of boil
20 min into the boil
5min near end of boil and
dry hop at end of boil

all was cascade

i made a german style lager and it had hops at the start then just at 5 min to go of two different types

my question is do certain times of boil equal certain flavors or in other words which ones are for bitterness and which ones are more for aroma?

cheers

 

[bconnery]

recently did a brew of little creatures pale ale and was wondering what the role was of adding certain hops at certain times of the boil?
for this recipe over a 60 min boil

at the start of boil
20 min into the boil
5min near end of boil and
dry hop at end of boil

all was cascade

i made a german style lager and it had hops at the start then just at 5 min to go of two different types

my question is do certain times of boil equal certain flavors or in other words which ones are for bitterness and which ones are more for aroma?

cheers

They do indeed.
Plenty of factors come in but very loosely speaking it works a bit like:
60-30/20 Bittering
30/20 - 5 Flavour
5- 0, Dry hop Aroma

Basically the longer you boil the more bitterness is extracted and the less flavour and the less aroma.
Beyond about 20 minutes the flavour aspect tends to disappear.
If you boil at all, or more than a few minutes, the aroma is lessened for the amount of hops you put in...

This all differs a little depending on the hops you use and the wort and other factors but loosely speaking...

 

[RobB]

In a very broad sense, we are interested in two things from hops: the alpha acids which contribute bitterness and the volatile oils which contribute the aroma and flavour.

For alpha acids to contribute the bitterness you want, they need to be chemically changed by boiling. The longer you boil them, the more bitterness you get. The problem with this is that it drives off most of those oils because they evaporate and breakdown pretty quickly.

So, the hops you add early add plenty of bitterness but you have driven off their flavour. The hops you add late don't have time to develop much bitterness, but you keep more of those lovely flavours.

I've seen a few of your recent posts and it looks like you're just starting to get your head around the science behind brewing. Have a look at John Palmer's book here:link. This is the first edition and it's free online. I think he's up to edition three or four now and I think it's worth having a copy on your shelf.

 

[hamstringsally]

They do indeed.
Plenty of factors come in but very loosely speaking it works a bit like:
60-30/20 Bittering
30/20 - 5 Flavour
5- 0, Dry hop Aroma

Basically the longer you boil the more bitterness is extracted and the less flavour and the less aroma.
Beyond about 20 minutes the flavour aspect tends to disappear.
If you boil at all, or more than a few minutes, the aroma is lessened for the amount of hops you put in...

This all differs a little depending on the hops you use and the wort and other factors but loosely speaking...

i keen as to start experimenting with some flavors of hops so i guess im just trying to understand the basic guidelines. is there basics for amounts of hops added as well?

for example add cascade at 60 and 30 for some bitterness, some galaxy at 15 for flavour and maybe amerillo for aroma? would this kind of attack work if i had the right amounts? it might not be a good mix but more just the understanding

cheers

 

[hamstringsally]

In a very broad sense, we are interested in two things from hops: the alpha acids which contribute bitterness and the volatile oils which contribute the aroma and flavour.

For alpha acids to contribute the bitterness you want, they need to be chemically changed by boiling. The longer you boil them, the more bitterness you get. The problem with this is that it drives off most of those oils because they evaporate and breakdown pretty quickly.

So, the hops you add early add plenty of bitterness but you have driven off their flavour. The hops you add late don't have time to develop much bitterness, but you keep more of those lovely flavours.

I've seen a few of your recent posts and it looks like you're just starting to get your head around the science behind brewing. Have a look at John Palmer's book here:link. This is the first edition and it's free online. I think he's up to edition three or four now and I think it's worth having a copy on your shelf.

thanks malty,

to be honest ever since i tasted that first all grain ive seemed to have lost my head. as i work through the day all i can think about is how cool brewing beer is and constantly wanting to learn more. its a hobby that is good in many ways i think.
thanks for your post mate

 

[Bribie G]

 

[bconnery]

i keen as to start experimenting with some flavors of hops so i guess im just trying to understand the basic guidelines. is there basics for amounts of hops added as well?

for example add cascade at 60 and 30 for some bitterness, some galaxy at 15 for flavour and maybe amerillo for aroma? would this kind of attack work if i had the right amounts? it might not be a good mix but more just the understanding

cheers

There isn't really a basic guide for amounts generally. In terms of flavour and aroma perhaps. For certain styles you'll often hear people talk of x grams per litre for flavour or aroma additions but overall it depends a lot on the SG of your beer, the style, the AA% of the hops etc. etc.
It's something you really need to read a bit about, play with a brewing calculator of some sort, read recipes..
That hop combo could work. I wouldn't worry about two bittering additions myself, just one at 60.
At a personal level I'd be inclined to bitter with the amarillo, flavour with galaxy and cascade and use cascade for aroma, but another brewer will have another opinion.

 

[MHB]

That graph is I believe WRONG.

I don't know who started posting it on AHB or where they got it, but some of the information is incorrect.

Aroma diminishes very rapidly once hops are put into a boiling wort, to be "aromatic something has to be volatile, which means it evaporates, everything evaporates faster when it's hotter.

Peak taste extraction is much closer to 10-15 minutes than the 20 shown.

The bitterness curve is complete rubbish

The earliest version I can find is on brewsupplies.com it's also been posted and argued about (discredited) on a number of other forums. It looks suspiciously like something made up to "prove" a point without reference to facts.

MHB

 

[Greg Lawrence]

That graph is I believe WRONG.

I don't know who started posting it on AHB or where they got it, but some of the information is incorrect.

Aroma diminishes very rapidly once hops are put into a boiling wort, to be "aromatic something has to be volatile, which means it evaporates, everything evaporates faster when it's hotter.

Peak taste extraction is much closer to 10-15 minutes than the 20 shown.

The bitterness curve is complete rubbish

The earliest version I can find is on brewsupplies.com it's also been posted and argued about (discredited) on a number of other forums. It looks suspiciously like something made up to "prove" a point without reference to facts.

MHB

Bugger, Ive been using that graph as a bit of a guide for some time now.
Are you saying that aroma hops should be at flame out?
Could you also elaborate more on the bittering curve?

Gregor

 

[MHB]

The big problem with brewing is that there is rarely 1 "Right" answer; there is more than one aromatic compound in hops. Some of the volatile fractions will evaporate faster than others, so longer or shorter boil times will change the aroma mix that remains in the beer form the same hop. That said in general; yes the total amount of hop aroma diminishes quite quickly once hops go into the kettle that may or may not be a good thing, depending on what you want from that hop in that beer.

There has been some very good research done by Shellhammer, using his equations I posted an excel spreadsheet here which describes how utilisation really works, it also allows a good understanding of what happens in no-chill cubes.

Just note that the yield of alpha is significantly higher than what you actually get into the fermenter or the finished beer for that matter, both hot break and yeast carry a certain amount of the IBU's away with them, and some just plain sticks to the fermenter and even kegs and bottles.

MHB

 

[hamstringsally]

There isn't really a basic guide for amounts generally. In terms of flavour and aroma perhaps. For certain styles you'll often hear people talk of x grams per litre for flavour or aroma additions but overall it depends a lot on the SG of your beer, the style, the AA% of the hops etc. etc.
It's something you really need to read a bit about, play with a brewing calculator of some sort, read recipes..
That hop combo could work. I wouldn't worry about two bittering additions myself, just one at 60.
At a personal level I'd be inclined to bitter with the amarillo, flavour with galaxy and cascade and use cascade for aroma, but another brewer will have another opinion.

thanks bconnery,

should i still use the LCPA grain mixture or are grain mixtures usually a standard mixture? Im going to give that one a go next brew just for the experiment side of things. it will be the first without following a recipe
i guess i just dont understand the grain side of things then to complete the experimental brewing side. are pale ale grain mixtures different to say a german lager mixture?
Ive ordered john palmer on amazon so hopefully ill get a truck load of info out of it.

cheers

 

[Screwtop]

At a personal level I'd be inclined to bitter with the amarillo, flavour with galaxy and cascade and use cascade for aroma, but another brewer will have another opinion.

I do Ben, how weird is that :lol:

use your brewing software to calc the amount from the AA of the hops, IBU's and your efficiency

Bitter using Galaxy for 60 min to 30 IBU

Amarillo at 40 min for about 3.5 IBU

Cascade at 1g/l at flame out and maybe dry hop after fermentation ceases.

:icon_drool2:

there is rarely 1 "Right" answer

Remember, this is very true!


Cheers,

Screwy

 

[hamstringsally]

I do Ben, how weird is that :lol:

use your brewing software to calc the amount from the AA of the hops, IBU's and your efficiency

Bitter using Galaxy for 60 min to 30 IBU

Amarillo at 40 min for about 3.5 IBU

Cascade at 1g/l at flame out and maybe dry hop after fermentation ceases.

:icon_drool2:




Remember, this is very true!

hey screwy,

what beer on the market that i could buy that is dominated or mainly made up of galaxy hops to give me a good idea of its characteristics?


Cheers,

Screwy

 

[hamstringsally]

hey screwy,

what beer on the market that i could buy that is dominated or mainly made up of galaxy hops to give me a good idea of its characteristics?

 

[jakub76]

I had a look at that excel spreadsheet MHB and it is interesting from a purely theoretical perspective. I notice there's no allowance for differences in wort gravity in the equasion. But what I found most interesting is that it seems that the utilisation peaks at around 150 minutes HOWEVER when I adjust the boil temp up to 110C it peaks around 63minutes. I have noticed that my boil is higher than 100C, I have a dial thermometer and it tops out at 106C and when I left it clipped onto the side of the pot last boil the needle was well and truly max-ed out. Perhaps all of the utilization tables we use assume a boil at 100C?

The big problem with brewing is that there is rarely 1 "Right" answer; there is more than one aromatic compound in hops. Some of the volatile fractions will evaporate faster than others, so longer or shorter boil times will change the aroma mix that remains in the beer form the same hop. That said in general; yes the total amount of hop aroma diminishes quite quickly once hops go into the kettle that may or may not be a good thing, depending on what you want from that hop in that beer.

There has been some very good research done by Shellhammer, using his equations I posted an excel spreadsheet here which describes how utilisation really works, it also allows a good understanding of what happens in no-chill cubes.

Just note that the yield of alpha is significantly higher than what you actually get into the fermenter or the finished beer for that matter, both hot break and yeast carry a certain amount of the IBU's away with them, and some just plain sticks to the fermenter and even kegs and bottles.

MHB

 

[glaab]

I think the chart is wrong too but it serves as a guide to answer the OP's question.
I added the black bitterness line from BS calcs

 

[MHB]

Either your getting a miss read (the thermo is touching the metal of the kettle) or thermometer is totally ted, or your boiling under a couple of bar of overpressure, there is no way you have a wort boiling at 106+ ^oC, 101-102 would be more like it.

But there is a fair amount of study going into over pressure boiling and more advanced kettles that require shorter boil times. Try putting 120 ^oC into that equation and see what happens. And as noted in the paper at a certain point the rate of decomposition of Iso-Alpha exceeds the rate of formation.

From what I can follow of the discussion (these guys are PhD level and most of the maths is well over my head) Wort Gravity isn't the issue, it's the amount of loss of Iso-Alpha and that is affected by the amount of Hot Break (naturally that's affected by wort gravity), no doubt there will be lots of other factors playing a role to.

There have been lots of ways to calculate "Utilisation" so far none of them is all that accurate, Tinseth in his work talks about "Boil Vigour" but that's just another way to view the energy in the system which is accounted for as a component of k₁ and k₂ in Shellhammers work. I've been playing around with the idea that evaporation rate could be used similarly as it is affected by both wort gravity and temperature (energy)

Frankly bitterness seams to go 30, 40, 50, 60 IBU's, OMG, Arrrrrrrrrr my mouths so dry I can't spit up to 90 IBU which is the limit.

Anyway I admit it IBU's is a hobby for me, I am more concerned with the misinformation portrayed in that graph as it relates to late additions. Bitterness isn't a problem, once we are talking very bitter just use lots of hops you really can't tell the difference over 70 ish IBU's.

My rule of thumb is taste additions at less than 20 minutes (generally 10)

Aroma additions as late as possible (in the whirlpool for me)

NOTHING between 20-50 minutes from the end; there are some hop components that we want to get rid of, they appear not go into solution in much less than 20 minutes and have been fully degraded or ejected within 50 minutes. As in all things brewing there are exceptions like that 45 minute addition in the middle of a Pilsner Urquell boil, I suspect that its less of a problem with older varieties of hops and more of a problem with modern high Alpha varieties, particularly American C Hop.

MHB

 

[manticle]

NOTHING between 20-50 minutes from the end; there are some hop components that we want to get rid of, they appear not go into solution in much less than 20 minutes and have been fully degraded or ejected within 50 minutes. As in all things brewing there are exceptions like that 45 minute addition in the middle of a Pilsner Urquell boil, I suspect that its less of a problem with older varieties of hops and more of a problem with modern high Alpha varieties, particularly American C Hop.

MHB

This last bit is interesting to me. Most beers I make have either a single 60 minute addition, a single 45 in the case of some low bittered UKs or a 60, 20 and 0. The few exceptions to that have been a small number of American style beers which, when I make them I'm tending towards hopbursting. I'll usually start at about 25 minutes with small amounts - a larger amount of bittering will have gone in at 60 and sometimes 45.

What unwelcome characteristics can hopping (with high aa type hops) in the 50-20 range bring?

 

[jakub76]

Sorry if this is a bit OT but I'm interested in differences in boil temps.

Either your getting a miss read (the thermo is touching the metal of the kettle) or thermometer is totally ted, or your boiling under a couple of bar of overpressure, there is no way you have a wort boiling at 106+ oC, 101-102 would be more like it.

I've double checked my thermometer and it actually tops out at 104C, that's as far as it's marked but the needle does go above that to where you would imagine 106 would be marked. I have checked it's accuracy compared to my digital temp controller and it seems fine.
My thermometer registers 100C when my wort is just starting to turn over, looks fairly turbulent, a few bubbles. At 102C I start getting what looks like a rolling boil with lots of bubbles. I keep my 2-ring burner going at full and like to get a vigorous boil happening. At that stage my thermometer is max-ed out above 104C.
Surely there's a temperature difference in a wort that's just ticking over and one that boiling violently. With all that sugar in solution it doesn't seem unlikely to me that it's reaching around 106C

 

[MHB]

For a sugar solution (that's what a wort is primarily) to have a boiling point of 106 ^oC you would need an SG of 1.280. The effect of both sugar concentration and pressure really are fairly exact sciences, here's a link on concentration.

Frankly it's not possible so there is either an error in the thermometer or the way it's being used.

MHB