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Decoction versus Temperature Mash

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mashweasel

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Post Thu May 04, 2006 2:11 pm

Tater tots and such and such

Im not going to get into the 'decoction' debate again. I have a few comments about protein rests though.

Nearly all of the protein degradation happens at malting, specifcally the germination step. When brewers talk about 'protein' rests, they seem to be talking directly about proteins. In all actuallity, it should be called a 'Nitrogen' rest. Yes, protein is the number one supplier of N2. However, most people fall to realize that starch goes to dextrins and Maltose anywhere from 14:1 - 10:1 ratio which is a MASSIVE degridation. When it comes to protein, we need to talk about solubilized N2.

Scientists have done tons of these types of experiemnts, basically using distilled water and mashing at 45C for 2hours. Their control is the same mash but using an protein inhibitor to stop all enzymatic activity. The difference is the soluble N2 in the malt itself. When you compare the malt N2 with the active sample you'll find a 1:1 - 1:1.6 ration of soluble protein. This is all dependent on HOW the malting was carried out much more so than the variety of malt used.

If we talk about proteinacious matter, we would see a 1:1 - 1:0.6 change. As you can see, this is VERY limited.

Going even futher, only about 1/3rd to 1/5 of this availible soluble N2 actually solubilzes and goes into solution of the final beer. This is taking into account hot and cold breaks.

Now we get to the sexy bit. Eventhough there is a very small amount of the total N2 that goes into solution, it is VERY important to the final beer. The hard thing is that each style is different. A style high in IBUs will have a ton of polyphenols that will form complexes with proteins and precipitate out. A beer that is fermented very high, around 158F, that doesn go through a rest at a lower temp will have a much more flabby pallate and mouthfeel than one that was.

The major players?? The medium size proteinacious fragments that one gets from rests anywhere from 35C - 60C...these are the players.

So what should you conclude?? For beers that are very straightforward, US/ UK ales and such, dont really need a protein rest b/c the malt character and mouthfeel arent that important for the overall character of style. On the other hand, very simple beers like single malt lagers, very much need it to get all the character possible out of the malt.

If you dont, will you get a bad beer?? Of course not. On the other hand, whats 20 mins or so.

One more note. No one doubts the effects of melanoidins for the flavor, aroma, color etc for beers. Most rely on the specialty malts to give this effect. Melanoidins are basically an amino acid combined with a sugar. When you look back and see the limited change of soluble N2 has and think about what effect can it possibly have...this is where it comes into play. Melanoidin fodder. That little change, when combined with heat and sugars, can and does have a dramtic effect to your finished beer. Both technically but most importantly, hedonically.
Egészségedre,

Kristen England, Ph.D.
BJCP Continuing Education Director
Grand Master Judge
http://www.bjcp.org
http://www.bjcp.org/cep


Homer Simpson - 'Homer no function beer well without.'
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BryanH

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Post Thu May 04, 2006 4:24 pm

Thanks, mashweasel, nicely put. That explanation sums up my results and feelings about the subject. A single conversion at sugar rest will make beer out of almost any available malt. The addition of a "protein" rest is an accessory available to the brewer to use as he/she may desire.
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Denny

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Post Fri May 05, 2006 10:51 am

Thanks, Kris, good info! Would you address the possible downsides of a protein rest with well modified malt, if there are any in your opinion? And also I'd like to hear your thoughts on a 122F vs. a 131ish F. protein rest. I appreciate your knowledge!
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Fatso

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Post Fri May 05, 2006 11:05 am

weas -

i assume you meant mashed at 158, rather than fermented at 158....
"A pint of your best bitter for me, and my young friend will have a laaager.... the gassier the better" - Tinker Dill
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nels

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Post Fri May 05, 2006 11:46 am

Kris,

Keep it coming. Btw...I loved the decoction debate.

What you're saying pretty much supports what I have read in multiple sources that very little protein degradation really occurs in the mash. I am confused by the last part, though. Are you saying that:

More N2 (protein) = more melanoidin and/or
protein rest = more melanoidins

I have never seen that before anywhere. I know that's one of the big benfits of a decoction, as boiling the grains releases more amino acids. But a simple protein rest? Please expound. I'd also like to hear your opinion on the temperature issue. Does a rest at 131 truly do a better job at breaking down the large proteins or does it just increase the activity and decrease the life span of the enxymes?

Jason Nelson
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mashweasel

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Post Fri May 05, 2006 12:16 pm

Sure, here are a few more thoughts on protein rests. A little pre-empt, for this writing im gonna use N2 in place of nitrogenous matter.

Soluble N2
As i said before, its basically the malting process that defines WHAT type of N2 the malt will posses. You will see a lot of scientific stuff talking about 'formol N2'. Basically what you are measuring is the soluble N2 content. Formol is a 10% Formaldehyde solution in water. When you add a clarified sample from malt to it you would then use NaOH to titrate out the sol N2. The sol N2 is what this is all about. If you cant solubilize some N2, it will not carry into the beer b/c its NOT in solution...hense soluble.

N2 Quality
People really do miss the point of the actually quality of N2. This at X temp gives this. Well, yes and no. Different size proteins that are formed at malting get broken down into specific sizes based on your mash temp. The high molecular weight proteins (HMW) lead to more head retention and mellowness of pallate. Low molecular weight proteins (LMW) lead to more colloidal stability. More on this in a tick.

Temperature
When we say protein rest, what we are talking about is a specific temp for a variety of enzymes. Proteinase, which break down HMW to polypeptides and peptones which are very heat stable. Peptidases, which break down polypeptides into amino acids and Free Amino Nitrogen (FAN), are VERY thermlabile. Most of them never make it out of the malting process. Their is very low activity at mashing and EVEN if you have a ton of them, their optimum pH is around 8.0...a million miles away from anything functional for a mash.

Professionally, in Germany anyway, they refer to this protein rest range as Peptonization Temperature 45C-60C (113-140F). As you can see this is a VERY large temp gradient. If one mashes on the low end of the scale, ~50C, you will gain the most N2. However, if you mash at the high end, 60C, there is still a ton of activity of which most people dont know.

So what does this mean to us? Many single infusion studies have been done with all types of malt. Its the common dogma that if you want a better mouthfeel you want as many dextrins as possible. A lot of people know this and will do a single infusion at 155-160F. Sure, you will get a ton of dextrins. The cool thing is that when compared against a beer that had an infusion over ANY of the range of temps for the protein rest and then up to the saccharification temp, these beers were deemed MUCH smoother and tasty. This will shock many people. When one does a rest at around 135F you get the best of both worlds. You get a lot of N2 but also you get a lot of those great HMW proteins that can only be said as 'delicious'.

Todays Malt
There are a lot of the german mash schedules that follow a double protein rest, 45C then 55-60C, and then a low mash and high mash. If you look back, the Germans have been making very good malt for a very long time. So for us to sit here and say, "Todays malt is so good you dont need to do X, Y or Z." is completely ludicris and even to the point of asininity. What it says to me is that our malt is VERY good which gives me even MORE chance to make it that much better by extracting everything I can possible extract out of it.

Question
What you're saying pretty much supports what I have read in multiple sources that very little protein degradation really occurs in the mash. I am confused by the last part, though. Are you saying that:

More N2 (protein) = more melanoidin and/or
protein rest = more melanoidins


Thats exactly what Im saying. The more N2 you have from the malting and mashing schedules the more melanoidins you can produce. Think of it this way, you have all the sugars you will ever need for producing melaniodins, the bottle neck is the amino acid and FAN stage. The more of each of these, the more possible melanoidins you can form.

This is scientific but also very practicle. Try it for yourself. Always question the dogma.
Egészségedre,

Kristen England, Ph.D.
BJCP Continuing Education Director
Grand Master Judge
http://www.bjcp.org
http://www.bjcp.org/cep


Homer Simpson - 'Homer no function beer well without.'
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nels

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Post Fri May 05, 2006 12:45 pm

Ok, thanks.

P.S. You need a new avatar - something a little more...controversial. Maybe a photo of this kid giving the middle finger salute to all the morality police?
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Big Stick Brewing Co.

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Post Fri Nov 02, 2007 5:15 pm

Re: Tater tots and such and such

mashweasel wrote:Im not going to get into the 'decoction' debate again. I have a few comments about protein rests though.

Nearly all of the protein degradation happens at malting, specifcally the germination step. When brewers talk about 'protein' rests, they seem to be talking directly about proteins. In all actuallity, it should be called a 'Nitrogen' rest. Yes, protein is the number one supplier of N2. However, most people fall to realize that starch goes to dextrins and Maltose anywhere from 14:1 - 10:1 ratio which is a MASSIVE degridation. When it comes to protein, we need to talk about solubilized N2.

Scientists have done tons of these types of experiemnts, basically using distilled water and mashing at 45C for 2hours. Their control is the same mash but using an protein inhibitor to stop all enzymatic activity. The difference is the soluble N2 in the malt itself. When you compare the malt N2 with the active sample you'll find a 1:1 - 1:1.6 ration of soluble protein. This is all dependent on HOW the malting was carried out much more so than the variety of malt used.

If we talk about proteinacious matter, we would see a 1:1 - 1:0.6 change. As you can see, this is VERY limited.

Going even futher, only about 1/3rd to 1/5 of this availible soluble N2 actually solubilzes and goes into solution of the final beer. This is taking into account hot and cold breaks.

Now we get to the sexy bit. Eventhough there is a very small amount of the total N2 that goes into solution, it is VERY important to the final beer. The hard thing is that each style is different. A style high in IBUs will have a ton of polyphenols that will form complexes with proteins and precipitate out. A beer that is fermented very high, around 158F, that doesn go through a rest at a lower temp will have a much more flabby pallate and mouthfeel than one that was.

The major players?? The medium size proteinacious fragments that one gets from rests anywhere from 35C - 60C...these are the players.

So what should you conclude?? For beers that are very straightforward, US/ UK ales and such, dont really need a protein rest b/c the malt character and mouthfeel arent that important for the overall character of style. On the other hand, very simple beers like single malt lagers, very much need it to get all the character possible out of the malt.

If you dont, will you get a bad beer?? Of course not. On the other hand, whats 20 mins or so.

One more note. No one doubts the effects of melanoidins for the flavor, aroma, color etc for beers. Most rely on the specialty malts to give this effect. Melanoidins are basically an amino acid combined with a sugar. When you look back and see the limited change of soluble N2 has and think about what effect can it possibly have...this is where it comes into play. Melanoidin fodder. That little change, when combined with heat and sugars, can and does have a dramtic effect to your finished beer. Both technically but most importantly, hedonically.


reading this takes all the fun out of brewing beer for me, It makes me feel like I may be doing something wrong, or should be doing something else
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Brewhobby

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Post Fri Nov 02, 2007 7:15 pm

Big Stick, are you trying to stir up trouble or are you seriously contemplating a question here? :wink: Either way....it's trouble....big trouble man....it's like throwing rocks at a hornets nest.....opening pandora's box......or maybe just another honest debate, I dunno....I've learned my lesson on this, it's a no win situation either way. I say try it, experiment with it....and see if you can tell a difference.
Primary- Czech Pilsner, IIPA
Secondary- IIPA, BVIP, Doppelbock, Baltic Porter
Kegged- A whole lotta beer
On Tap- Helles, Pale Ale, Rye IPA
Next Up- BVIP, IPA
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wofat

Post Fri Nov 02, 2007 8:33 pm

I sort of agree. While I consider myself a highly technical brewer, and very anal about my temps, etc... I have not yet been able to detect the difference between my Helles with a decoction, vs my Helles with a multi-step rest, vs my Helles done in a single infusion. Call me crazy, but I'm going with the 'straght line' theory.
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TG

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Post Fri Nov 02, 2007 8:42 pm

What exactly is a "flabby mouthfeel"?
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Pawtucket Patriot

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Post Fri Nov 02, 2007 8:52 pm

TG wrote:What exactly is a "flabby mouthfeel"?


Not sure if the beer definition completely correlates to the wine definition, but oenologically speaking (nice word, eh?), "flabby" is a word used to describe a wine with little structure. It can also refer to the mouthfeel of a wine that lacks acidity. So, if I were to venture a guess as to how that relates to beer, I would say it probably means a slightly watery mouthfeel without a malt backbone.
Last edited by Pawtucket Patriot on Sun Nov 04, 2007 6:54 pm, edited 1 time in total.
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Brewhobby

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Post Fri Nov 02, 2007 9:24 pm

TG wrote:What exactly is a "flabby mouthfeel"?


Hmmmm, I guess it's kinda like drinking water(one example anyway). Here's another......The morning after you drank WAYYYYYY too many homebrews.....and you happen to have some gatorade sitting around....it's a little watery and thin but still tastes good, AND it does the job. Yeah, it's hard to describe..... :wink: I guess another way to describe it is......there's just something missing but can't really put a finger on it.....complexity??? Who knows...
Primary- Czech Pilsner, IIPA
Secondary- IIPA, BVIP, Doppelbock, Baltic Porter
Kegged- A whole lotta beer
On Tap- Helles, Pale Ale, Rye IPA
Next Up- BVIP, IPA
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Geronimo

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Post Sun Nov 04, 2007 6:29 pm

wofat wrote:I sort of agree. While I consider myself a highly technical brewer, and very anal about my temps, etc... I have not yet been able to detect the difference between my Helles with a decoction, vs my Helles with a multi-step rest, vs my Helles done in a single infusion. Call me crazy, but I'm going with the 'straght line' theory.


I've been doing my best to realize some differences, too. I have to admit, with beers starting at 1.068 to 1.085 OG the differences were meaningless if they existed. I've read backwards to all the original debates on these topics and see that Mashweasel is describing 5 gallon batches using only ~9 lbs of grain for an OG of roughly 1.050.

So, it could be that relatively low gravity beers reveal subtle differences, or... that most of us don't have the sensitivity in our senses to detect the differences.
-- Jim
home brewing in Minnesota
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