Longer Boil...

[mongrell]

Besides hops and AA% and IBU, what difference does the boil make. Does a longer boil do anything else for the beer besides bitterness. Does it help break down the malt proteins or something?

 

[boo boo]

A longer boil will get you more hot break. increase the colour, increase ( to a point ) the malty flavour, in addition to extracting the max bitterness out of your hops. A lot of big micro brewers do boils of at least 90 minutes ( from " Secrets from the Master Brewers" )

 

[TheCrane]

Longer boils will caramelize more of the sugars present in wort. This has a pronounced effect on malt profile of the finished beer. In styles where this is desirable, such as scotch ales, boils of many hours are often used. Another obvious consequence is that you will remove more water with a longer boil. This will increase your OG, and subsequently alcohol content and overall character.

 

[TexLaw]

Longer boils also can help remove volatile compounds, such as DMS, when they can be a problem.


TL

 

[Kaiser]

If you boil to long (lets say past 120 min) you will start hurting head retention by coagulating to many proteins.

Kai

 

[Ryanh1801]

If you boil to long (lets say past 120 min) you will start hurting head retention by coagulating to many proteins.

Kai

Just wondering what thats based on? I have never been able to do less than a 120 min. on most of my beers, because of my slow evaporation rate. On a big barley wine I had a 8 hour boil before starting my hop schedule, I have not noticed and reduction in head retention, in fact it stays present until the beer is gone.

 

[Jack]

Kaiser, I haven't heard that. However, if it were true you could add a small amount of fresh DME or dried malted wheat extract or something say 15 minutes before flame-out. That way you'd add fresh protein and you would get ok head retention even with a long boil.

Not to hijack this thread, but it's sort of related.

I've been reading Radical Brewing and he talks about how some Belgian ales were traditionally boiled in the range of 6-8 hours to caramelize the sugars resulting in an inimitable flavor development and unique color.

Some questions:
1. Has anyone tried an insanely long boil?
2. Do you end up with a monster of a beer or do you top it off with water periodically to maintain a relatively stable volume?
3. I've heard recommendations against leaving your oven on too long (like don't try heating your home with your gas oven, you'll die). Would it be potentially risky to leave a burner on inside for that long?

 

[Kaiser]

Just wondering what thats based on? I have never been able to do less than a 120 min. on most of my beers, because of my slow evaporation rate. On a big barley wine I had a 8 hour boil before starting my hop schedule, I have not noticed and reduction in head retention, in fact it stays present until the beer is gone.

I found this in a German brewing textbook. It doesn't give a time there, but notes that if the protein coagulation is to complete the wort will loose to many of the longer chained proteins and the headretention and mouthfeel will suffer.

Yesterday I came across this (it's a German Beer taste evaluation sheet) and it talks about a boil-taste that is developed after 100 min of boiling. But I have no idea what that tastes like and what their reference is.

I have never boiled a wort for longer than 90min myself, so I cannot comment on the affects of a long boil.

Kai

 

[Ryanh1801]

I found this in a German brewing textbook. It doesn't give a time there, but notes that if the protein coagulation is to complete the wort will loose to many of the longer chained proteins and the headretention and mouthfeel will suffer.

Yesterday I came across this (it's a German Beer taste evaluation sheet) and it talks about a boil-taste that is developed after 100 min of boiling. But I have no idea what that tastes like and what their reference is.

I have never boiled a wort for longer than 90min myself, so I cannot comment on the affects of a long boil.

Kai

Interesting, ill have to see if I can read that over, with my limited German skills.

 

[Rhoobarb]

I only brew one beer that has a longer boil time than 90 mins. My CWS IIPA (see my recipe drop down) goes for 110 mins. It's been a real crowd pleaser every time I've brewed it. Never noticed anything unusual vs. my 60 & 90 min boils.

Some of us local HBT'ers met up last Saturday and the subject of 90 min vs. 60 min. boils came up. It seems a lot of us either prefered or were starting to prefer 90 min mash/boils vs. 60 min. For me, I seem to get better effeciency and hit my OG more dead on.

 

[homebrewer_99]

The maximum hop bitterness extraction is at 60 mins. You can't get any more from it if you boiled for 5 hours.

The main reason for longer boils is to reduce the liquid through evaporation. And that is only important if you are precise in your measurements and are trying to reach a specific OG and quantity.

 

[TheCrane]

The maximum hop bitterness extraction is at 60 mins. You can't get any more from it if you boiled for 5 hours.

This isn't exactly true. Utilization will continue to go up past 60 min, however not by a whole lot.

The main reason for longer boils is to reduce the liquid through evaporation. And that is only important if you are precise in your measurements and are trying to reach a specific OG and quantity.

Longer boils will caramelize more sugars as well, changing the malt character profile and fermentability of the wort, as well as color.

For me, I seem to get better effeciency and hit my OG more dead on.

Technically, your efficiency has not been changed, only the volume. Efficiency is based on the total amount of sugar extracted from a your grains, divided by the amount present in said grains. Boiling down only concentrates what you have collected.

 

[homebrewer_99]

This isn't exactly true. Utilization will continue to go up past 60 min, however not by a whole lot.

Got that anywhere I can read it...I'm interested...

 

[TheCrane]

http://www.howtobrew.com/section1/chapter5-5.html
http://www.realbeer.com/hops/research.html
http://www.strandbrewers.org/techinfo/hopcalc.htm

For starters

 

[Moonshae]

3. I've heard recommendations against leaving your oven on too long (like don't try heating your home with your gas oven, you'll die). Would it be potentially risky to leave a burner on inside for that long?

That's because people make house fires that way.

 

[SavageSteve]

Longer boils will caramelize more sugars as well, changing the malt character profile and fermentability of the wort, as well as color.

I'm interested in learning more about this, specifically the changes in fermentability-- do you have any references?

-Steve

 

[Ryanh1801]

The maximum hop bitterness extraction is at 60 mins. You can't get any more from it if you boiled for 5 hours.

The main reason for longer boils is to reduce the liquid through evaporation. And that is only important if you are precise in your measurements and are trying to reach a specific OG and quantity.

Im boiling down to volume, not starting my hop schedule, I boil down to 6 gallons then start my hop schedule.

Not sure if you are talking to me or not.

 

[Kaiser]

the changes in fermentability

I don't think you get a lot of that.

from the brewing text book I like to cite from a lot (translation)

... It deserves mentioning that the maillard products formed during kilning are in the broadest sense malty but pure tasting flavor components while the [maillard products] formed during the boil produce undesirable changes.

from Fix quoting Narziss

... Of all wort reductones, the simple melanoidins in their reduced state are the most desirable. They have an attactive toasty flavor in amber and dark beers. Similar results can be achieved with worts produced from infusion mashes if boiling is properly conducted. On the other hand excessive thermal loading can transform the simple melanoidins into less desirable heterocyclics as described next ...

The Fix quote basically states that you can generate desirable flavor components if you keep the thermal loading of the boil low. Later he says that this should be given if the evaporation rate is less than 10 - 11%/hr

Statements like this make me skeptical of long boils. You may try to brew one of your bigger recipes with a shorter boil and malt extract additions to make up for the gravity boost you are getting from the longer boil and see if you like the result better or less.

Again, just quoting the books here. I would have to taste a 2+ hr boil beer to make a judgement.

Kai

 

[homebrewer_99]

Im boiling down to volume, not starting my hop schedule, I boil down to 6 gallons then start my hop schedule.

Not sure if you are talking to me or not.

I wasn't speaking to anyone in general...,but boiling down usually refers to all grainers. Extract brewers don't do it.

 

[TheCrane]

I'm interested in learning more about this, specifically the changes in fermentability-- do you have any references?

-Steve

Busted!! Allow me to rephrase: Effects flavor, color and presumably fermentability.

My understanding of caramelization (no doubt a modest one) is that sugars (ie sucrose, fructose, maltose etc..) react with water under heat in a long series of complex reactions that produce compounds including biacetyl (C4H6O2; buttery smell, and taste) and even larger molecules such as caramelans (C24H36O18) and caramelins (C125H188O80) which add color. Presumably these are not fermentable. However, as we are talking about a boiling wort which is ~200 F, and these reactions take place at substantially higher temps, these conversions may be minimal, as they are limited to the hot surface at the bottom of your kettle, and perhaps any change in fermentability may be undetectable. I applaud your demand for credability:cross:

 

[Rhoobarb]

...Technically, your efficiency has not been changed, only the volume. Efficiency is based on the total amount of sugar extracted from a your grains, divided by the amount present in said grains. Boiling down only concentrates what you have collected.

True. I was referring more to 90 min. mash vs. 60 min. Should have clarified that.

 

[SavageSteve]

Busted!! Allow me to rephrase: Effects flavor, color and presumably fermentability.

I was really just trying to get more info! After reading your post, I started Googling "wort caramelization" and quickly fell into the rabbit hole. I emerged a long while later with exactly what you stated: that perhaps only a small amount of sugars are converted into something that isn't fermentable (given good boiling conditions).

My main concern with regards to my own brewing is making sure I get proper attenuation during fermentation. I've struggled for a while with a high residual SG and have been trying to solve it once and for all, and when I read your comment, I thought that perhaps that could be the cause. In reality, though, I believe I have solved the problem with higher yeast pitching rates and injecting oxygen into the wort.

I applaud your demand for credability:cross:

Thanks! I am a scientist and skeptic at heart, and my first reaction to any claim is, "Where's your evidence?"

Cheers,
Steve

 

[as_saturn_ascends]

Actually you all may be interested in knowing that sugar carmelizes at 375deg F. Carmelization affects color when baking cookies and brewing beer. Thought that might be something you would like to hear. I know in my kettle it could be easy to go over 375deg. and if you use a fire probably even easier. thats probably why Kaizers source says not to go past 10-11% evaporation rates. any hotter carmelization might start...???? im not sure.

and i have no idea what it does for fermentability.

a quick lookup on French Sous Vide cooking may help. its the art of holding food at certain temps to cause certain reactions. and not other reactions.

 

[wonderbread23]

I know in my kettle it could be easy to go over 375deg. and if you use a fire probably even easier. thats probably why Kaizers source says not to go past 10-11% evaporation rates. any hotter carmelization might start...???? im not sure.

Pretty sure your kettle will never get that hot. With a solution of a normal wort, it is gonna basically hit 212 and plateau. The higher temperatures of carmelization occur in in super saturated sugar solutions. Now maillard reactions.... that seems to be where the real effects of long boils come in to play.