The Effects of No Chill on Hop Utilisation

[MyQul]

I've noticed a lot of members are now starting to no-chill their wort (or are considering trying it out). This may have something to do with the success of Clibit's Simple AG thread. Members are trying out AG via Clibit's thread, finding they like it, but are wanting to up volumes made from 5L. Members then realize it's increasingly hard to cool 10L/15L/23L, without a wort chiller so are looking at no-chill as a possible answer.

Wort chillers can be expensive, around £50-£60 so a new AG brewer may not want to spend that kind of money early on in their AG brewing career. For those of you reading this, and who are unaware, ManseMasher is selling DIY immersion chillers at cost plus P&P for his first response charity

http://www.thehomebrewforum.co.uk/showthread.php?t=55234

Its pretty simple to no-chill. Just put the near boiling wort in a cube/FV/kettle, take a few simple precautions against infection. Then pitch your yeast the following day when your wort is cool.

But as per the title of this thread, leaving hops in near boiling wort has effects upon hop utilisation.

Bittering Addition

If you leave your hops in the wort overnight whilst the wort is cooling your final beer will end up more bitter than planned, as the hops will continue to isomerize in the wort till the wort reaches 79C.

There are two ways i know to deal with this. This simplest, which is what I do is to seive the hop debris out of the wort as you transfer the wort from your pot to your FV.
The second way is to boil for two hours. AFAIK hop utilisation severly tails off/stops altogther after two hours. So if you do a two hour boil you will be able to calculate your bittering addition based on this (I understand that hop utilisation finishes after 2 hours and read this third hand and need to confirm this. So if in doubt use method one and simply seive the hop debris out)

Flavour/Aroma Late Additions

Hop oils are volatile. So if you add your late additons during the regular boil the flavour and aroma can vapourize and get carried away with the steam whilst your wort is cooling down.

There are also two ways I know to deal with this. The first is 'micro boils' (I have yet to come across a name for this method so have just christened it 'micro boils').
The following day, when your wort is cool. Draw off about 3L and bring to the boil. You need to boil the drawn off wort for the micro boil for at least 15 mins to re-sanitise it.
You can then add your late additions as normal to the micro boil. So if you have a 15min addition, 5 min addition and flameout addition, put the 15min addition into the wort as soon as it come to the boil, the 5 min addtion five mins from the end of the boil and with the flame out addition, cool the wort to 80C then steep the flame out addtion for 20 mins
Of course if you have 20 or 30 min addition you would need to boil your wort for longer.
Then cool the micro boil in the sink with some cold water. You don't need to cool it all the way back dow to room temp as adding 3L to 20L wont have that much temperature effect on the main body of the wort - cooling the micro boil down to 50C or so will do.Then just add the micro boil to the main body of wort and pitch your yeast

The second way of dealing with hop oil vapourisation is hopstanding. This is basically, cooling the wort to 80C then adding your hops at 'flame out'. I haven't looked into this technique much but from the little I've read, adding a flame out addition and then leaving your wort to cool overnight has the same effect as a regular 20 min addition.

Another forum member linked this article on hop stand to another thread

https://byo.com/component/k2/item/2808-hop-stands

I've yet to read it fully. Hop stands to deal with the effect of no chill on hop utilisation is an area I know little about at the moment but it's an area I intend to investigate. But at the moment as far as I know it is a method that when used correctly can counter the effect of the oils from the hops vapourizing.

Chill Haze

This isn't really anything to do with hop utilisation but as I have written this guide with new AG brewers in mind, I wanted to make anyone who wasn't aware, of one of the 'down sides' of no-chilling.

From How to Brew by John Palmer

http://www.howtobrew.com/section1/chapter11-8.html

[FONT=Verdana, Arial, Helvetica, sans-serif]When cooled prior to serving, some batches will exhibit chill haze. It is caused by proteins left over from those taken out by the cold break. The proteins responsible for chill haze need to be thermally shocked into precipitating out of the wort. Slow cooling[or no chilling - my addition] will not affect them. When a beer is chilled for drinking, these proteins partially precipitate forming a haze. As the beer warms up, the proteins re-dissolve.
Chill haze is usually regarded as a cosmetic problem. You cannot taste it. However, chill haze indicates that there is an appreciable level of cold-break-type protein in the beer, which has been linked to long-term stability problems. Hazy beer tends to become stale sooner than non-hazy beer.


Personally I'm not effected by chill haze as I always drink my beer at room temp, whatever that may be, throughout the year. I've also never noticed any staleness but then again my beer never lasts more than 6 weeks

[/FONT]
I think this 'guide' is more of a work in progress then a full guide at the moment due to the gaps in my knowledge (particularly about hop stands), so welcome any feedback, input or critisism. I've written this 'guide' more with a mind to make new AG brewer aware, that there are things to watch out for if they choose the no-chill route. When I start to begin to look into hop standing I will update this thread

 

[ProjectBeer]

Quick question with regards to your mini boil to deal with the late additions - won't the hop utilisation be much lower than in the full volume boil due to the smaller amount of water it's boiled in?

Will you need to take that into account when calculating the bittering additions or is it too minimal to be worth bothering with on a homebrew scale?

 

[MyQul]

Tbh I don't know the answer to that question.* I don't know if volume has an effect on hop utilisation in a similar way that wort density (gravity) has.
I think if it as comparable to when I do my main boil in a more concentrated wort (Maxi-BIAB). I only need to add an extra 5 IBU to compensate and I know from BIAB forums that some maxi-biabers don't bother adding any extra because the difference is so small

So I suspect in a similar way to you that the volume is so small that it has minimal effect

*I boil the late additions in wort not water but I think you meant wort didn't you?

 

[ProjectBeer]

Yup, I mean wort. I thought it might not make a difference, but wasn't sure!

 

[rodabod]

I'm not sure if removing the hops before the extended chill will stop further isomerisation: my understanding was that it's the dissolved solids in the wort which will isomerise, and not the hops themselves. So any additions before chilling will have a great chance to isomerise, even if you remove the hops. Removing the hops makes sense though, as you'll have more control of bitterness extracted. Bitterness units continue to extract beyond 1hr, so I'm not sure how much more bitter a wort would end up if you left the hops in, and let's say it maintained >80c for another hour.

The bitterness extraction is relative to the volume boiled, but I think your "micro boil" suggestion still sounds relevant if you have no option but to have an extended chill. I reckon you could be smart about it and steep the hops at different temperatures. Could for example run a very small boil for 60s and immediately dilute this volume with cold wort to run a mimic whirlpool temperature for a number of minutes, etc.

If it were me though, I'd just find a way to chill it. A sink and ice water has sufficed for me in the past.

 

[Twostage]

Quick question with regards to your mini boil to deal with the late additions - won't the hop utilisation be much lower than in the full volume boil due to the smaller amount of water it's boiled in?

Will you need to take that into account when calculating the bittering additions or is it too minimal to be worth bothering with on a homebrew scale?

I looked into the 'what happens if I boil hops in a tiny amount of water and then add it to the brew' question a couple of months ago. If brewmate is right then boiling hops in 500ml and adding it to 9.5 litres is very similar to boiling the hops in 10 litres.

I've done it a few times with extract brews (such as my lava lamp). I once tasted the hop tea and I can confirm that it sucks your mouth dry.

 

[MyQul]

Quick question with regards to your mini boil to deal with the late additions - won't the hop utilisation be much lower than in the full volume boil due to the smaller amount of water it's boiled in?

Will you need to take that into account when calculating the bittering additions or is it too minimal to be worth bothering with on a homebrew scale?

My next brew (today - have got an all day mash on at the mo) is an Ordinary Bitter of OG 1.035. After some discussion with Clibit on this a couple of days ago I decided to input the figures for a 3L (which is what I usually take out to do the mini boil) brew length of 1.035 with the 6.8 grams of First Gold (AA% 8.3) for 10mins, which is the late addition for this brew.

On the full 23L brew that 10min boil adds 2.35 IBU. However, when I inputted the fugure for a 10min boil in 3L alone, I was astounded to get a calculation of an additional 16.45 IBU :shock:

Intuition would lead most people to think (including myself), because of the lower volume you boil the hops in you'd get much lower utilisation (and therefore less IBU's of course) not more!

This throws into relief some of the results of some recent bitters I made. I always assumed that the extra harshness I was getting in my bitters was due to incorrect water chemistry for this style. Also my last ESB has a solvent/fusil like flavour in it despite the fact I fermented it at between 19C-22C. Having googled solvent flavour in beer, one of the causes is over hopping.

As MM says, 'every day's a school day'

 

[clibit]

The 16.45 IBUs are in 3 litres of wort. When you add it to the rest of the wort, it is diluted.

23 / 3 = 7.66666

So the IBUs will be diluted 7.66666 times.

16.45 / 7.66666 = 2.15 IBUs. (rather than 2.35 IBUs)

So there is a reduction in hop utilisation.

This assumes that the software is right, and it's very difficult to calculate the effect of boiling hops in different amounts of wort which may have different gravities. We also don't know the true AA% of any small batch of hops.

 

[MyQul]

The 16.45 IBUs are in 3 litres of wort. When you add it to the rest of the wort, it is diluted.

23 / 3 = 7.66666

So the IBUs will be diluted 7.66666 times.

16.45 / 7.66666 = 2.15 IBUs. (rather than 2.35 IBUs)

So there is a reduction in hop utilisation.

This assumes that the software is right, and it's very difficult to calculate the effect of boiling hops in different amounts of wort which may have different gravities. We also don't know the true AA% of any small batch of hops.

Ah, of course. Forgot the 3L/16.45 is then diluted by the main body of the wort.

 

[MyQul]

I've been thinking (always a dangerous thing), hop teas add flavour and some aroma and dry hopping adds aroma and some flavour. So I'm thinking of add my late addition as hop tea/dry hops. Anyone see a flaw in my cunning plan?

 

[dad_of_jon]

I've been thinking (always a dangerous thing), hop teas add flavour and some aroma and dry hopping adds aroma and some flavour. So I'm thinking of add my late addition as hop tea/dry hops. Anyone see a flaw in my cunning plan?

apart from calculating the abv correctly as there is now a top tea addition after the og was taken, no.

The only hop tea I did went in before pitching the yeast but of course I took my og after that. The subsequent fermentation of course removed some of the hop flavour/aroma. if anyone has a way to calculate the abv correctly with a 500ml or 1 litre hop tea addition that would be great :-)