Extracting Hop Aroma And Flavour With Pressure

[megs80]

Hey all,

I came across this on a food science blog the other day. It involves using pressure to extract flavour and aroma into a liquid using pressure. At the moment I no chill my beers and have been wondering the best way to get a good hop forward beer with this method.
Im going to give this a go next brew by just adding 40 or so grams of hops to some warm water then straining into a keg of beer, I own an isi whip and have a load of charges but my thoughts are is you dont, maybe a plastic bottle with a carbonation cap using C02 would work just as well?
Anyway, thought it might be intersting as lots of us love hops and no chill.

Cheers

http://blog.khymos.org/2010/08/21/wonders-...ction-pressure/

 

[MarkBastard]

 

[Fents]

i dont understand all this no chill vs no hop flavour / aroma. (even dont see a need for french press aka coffee plunger)

either cube hop your cube or just dry hop your fermenters at about day 3 or 4 of primary with approx 1g/L and you get hops jumping out at you.

 

[Bribie G]

i dont understand all this no chill vs no hop flavour / aroma. (even dont see a need for french press aka coffee plunger)

either cube hop your cube or just dry hop your fermenters at about day 3 or 4 of primary with approx 1g/L and you get hops jumping out at you.

Mark and I are cheap bastards
No not really, but it's a pity to pay big money for stuff that you chuck away. In the case of hops used for late hopping, you are throwing the baby out with the bathwater because all those lovely Alpha Acids etc are wasted in pursuit of the hop flavours and aroma. One procedure you can do with the french press is to:

Before the brew, French press your aroma hops. Put the hop tea into a sterile jar in the fridge.
Use the pressings (I find it works best with flowers) as part, or even all, of your bittering addition in the kettle. (edit: in the case of a SMASH brew. I've had cracking results with Hallertau + no chill doing this)
If no chilling, don't add any further hops until the wort goes into the fermenter. Then add the jar of yumminess into the fermenter.
What you are doing is to 'fractionate' the hops so that the aroma component gets 'quarantined' until after the no chill cube. Another thing you could do is to pour the jar into the cube once the temp has dropped below 80 degrees, but I don't like to open the cube personally.

As for using pressure, I'm not sure how that would work exactly?

 

[Fents]

if your chasing flavour and aroma from a hop how is that wasting it? if we were talking commercial quantities i could understand but in 20L - 100L batch? seriously hops are about $1 for 10 grams.

 

[widdley]

What you are doing is to 'fractionate' the hops so that the aroma component gets 'quarantined' until after the no chill cube.

Love it! :beerbang:

 

[megs80]

Mark and I are cheap bastards
No not really, but it's a pity to pay big money for stuff that you chuck away. In the case of hops used for late hopping, you are throwing the baby out with the bathwater because all those lovely Alpha Acids etc are wasted in pursuit of the hop flavours and aroma. One procedure you can do with the french press is to:

Before the brew, French press your aroma hops. Put the hop tea into a sterile jar in the fridge.
Use the pressings (I find it works best with flowers) as part, or even all, of your bittering addition in the kettle. (edit: in the case of a SMASH brew. I've had cracking results with Hallertau + no chill doing this)
If no chilling, don't add any further hops until the wort goes into the fermenter. Then add the jar of yumminess into the fermenter.
What you are doing is to 'fractionate' the hops so that the aroma component gets 'quarantined' until after the no chill cube. Another thing you could do is to pour the jar into the cube once the temp has dropped below 80 degrees, but I don't like to open the cube personally.

As for using pressure, I'm not sure how that would work exactly?

Nice idea, I hadent thought about saving the hops once pressed and using them as bittering.

The concept of using pressure is the liquid is forced into the cells of the stuff your trying to get the flavour from eg hops. When the pressure equallizes the liquid leaves the cells with the volitiles.

 

[QldKev]

My coffee plunger is gold in color, will it still be ok to use? :huh:

QldKev

 

[Nick JD]

I've done similar to BribieG quite a bit, but I use my dryhops that were floating in a hopsock as the bittering addition in a subsequent batch.

A bonus is that a lot of the flavour/aroma compounds have leached into the previous brew making use of these hops bittering only.

Nelson Sauvin is the hop that taught me just how much flavour is stripped out - I used flavour stripped NS as the 60 minute addition of the next brew and there was zero NS flavour - and not tasting NS in a 60 minute addition is unpossible. Like using isohop, almost - great for beers with no hop character wanted.

That's 30IBUs going in the bin!

 

[Bribie G]

Nice idea, I hadent thought about saving the hops once pressed and using them as bittering.

The concept of using pressure is the liquid is forced into the cells of the stuff your trying to get the flavour from eg hops. When the pressure equallizes the liquid leaves the cells with the volitiles.

Aha, ok, that's what Carlton Do with 'supercritical' CO2 when they make their hop extracts, and it extracts more than just the isohop. That's why (and this had puzzled me) Melbourne Bitter actually has a bit of hop character, not just the bitterness. Also some German breweries like Oettinger do that as well according to their bottles and cans "hopsextract". :blink:

As far as $$ go, with the likes of Hallertau and other lowish AA hops (also the likes of EKG) fifty or sixty grams of hops over 50 brews starts to add up :icon_cheers: But obviously no benefit in doing it with the high alpha bitterers like Northern Brewer, POR etc.

 

[drsmurto]

I've refrained from commenting on this cost saving method for a while now but....

Exactly how do you know how to calculate your IBU contribution of the hops after they have been french pressed? Are you making the assumption that none of the lupulin that contains the alpha acids is in the liquid and remains in the hop cones?

 

[Bribie G]

Still a work in progress, and you are right, it's hard to know how much IBU is left in the pressings. However I've only been doing this in beers I make for my own enjoyment and it's more a case of "go on surprise me" - so far it has made some interesting beers and I'll continue to do so. However I take your point that it's not something you might want to do with a brew where you are aiming to hit a bang on profile for a comp.

 

[Nick JD]

Still a work in progress, and you are right, it's hard to know how much IBU is left in the pressings. However I've only been doing this in beers I make for my own enjoyment and it's more a case of "go on surprise me" - so far it has made some interesting beers and I'll continue to do so. However I take your point that it's not something you might want to do with a brew where you are aiming to hit a bang on profile for a comp.

I've found that hops that have been dry hopping (@12C) for 4 days still get me my intended IBUs. The french press method surely wouldn't strip any bitterness?

 

[drsmurto]

I've found that hops that have been dry hopping (@12C) for 4 days still get me my intended IBUs. The french press method surely wouldn't strip any bitterness?

It wont strip bitterness but you are adding the hops to boiling water or close to and the lupulin which contains the alpha acids and the aroma molecules will be in suspension if not partly/completely dissolved in the water. This wont extract bitterness as you still need extended boiling to isomerise the alpha acids.

So you are reducing the amount of alpha acids which in turn will reduce the amount of iso-alpha acids in the next beer.

I have no problem with people experimenting but I'd hate to see a new brewer take up this method as a way of saving money only to find a variable bitterness in their beer.

 

[Nick JD]

It wont strip bitterness...

So you're saying that a hop sock with 20g of NS put into a fermenter for 4 days, removed at bottling and then put in another brew's boil will have lost some of its bitterness compounds and will not achieve the assumed IBUs?

Can you give me some references to why and how this is happening? I don't find this is the case in practice.

I thought that the french press method used cold water to steep the hops...

Oh, and I recommend my dry hop reuse to all new brewers. It'd be a dull world if we all just made JSGA clones.

 

[felten]

here we go again

 

[DangerousDave]

why do you have an isi whip and a load of charges h34r:

 

[drsmurto]

So you're saying that a hop sock with 20g of NS put into a fermenter for 4 days, removed at bottling and then put in another brew's boil will have lost some of its bitterness compounds and will not achieve the assumed IBUs?

Can you give me some references to why and how this is happening? I don't find this is the case in practice.

I thought that the french press method used cold water to steep the hops...

Oh, and I recommend my dry hop reuse to all new brewers. It'd be a dull world if we all just made JSGA clones.

The lupulin glands contain both the alpha acids and the aroma compounds (essential oils). If you are assuming that mixing hops with water extracts aroma using the french press method then logically the alpha acids will also be extracted to some degree.

When you strain out the hops for reuse later you will have lost some of the alpha acids to the hop tea you have made. As i stated earlier, you wont extract bitterness and boiling is required to isomerise alpha acids.

When you come to reuse the hops for bittering you will have less alpha acids present than if you were to use 'fresh' hops. Therefore you will have less bitterness.

I don't have any references for you Nick, this is based on a little bit of logic and my background in synthetic chemistry. If you are happy with what you are doing and your results then this debate is pointless, all i am trying to do is add an alternative view point to give others something to think about.

If you were interested in looking into this further i would suggest searching for the solubility of alpha acids in water at varying temperatures to work out what % of alpha acids you are removing by steeping them first. While you are at it you could see what the difference in solubility is when the 'steeping' solution used contains sugars/proteins etc.

Cheers
DrSmurto

 

[MarkBastard]

Anyone tried using an espresso machine to make a 'hop tea'?

Don't they work with high pressure hot water passed through a material? Seems like it could be ideal.

 

[Malted]

Anyone tried using an espresso machine to make a 'hop tea'?

Don't they work with high pressure hot water passed through a material? Seems like it could be ideal.

I reckon I will give that a go just for shits and giggles!