Mashing duration's impact

[TimboSlice]

I'm new to brewing, maybe a naive question, but I was curious about mashing. When I'm mashing does the mashing duration being longer make it more malty or more sweet? So if I shorten the time will it be sweeter or more malty? Thanks for the insights

 

[unionrdr]

Longer mashes can bring out other flavors,as in the Burton ales of old. But dryer or sweeter is more a function of mash temp. Say around 152F for average beers,155-158F for sweeter heavier malt flavors. Low end more fermentable,high end less fermentable.

 

[tgmartin000]

A longer mash time can result in a more fermentable wort, leading to a dryer beer. Shorter mash times mean more long-chain dextrins in your wort, giving more mouthfeel and maltyness, but not necessarly 'sweet'.

 

[BigFloyd]

It really depends on what you mean by a longer mash time. An extra 10-15 minutes? An hour more? Overnight?

 

[unionrdr]

A longer mash time can result in a more fermentable wort, leading to a dryer beer. Shorter mash times mean more long-chain dextrins in your wort, giving more mouthfeel and maltyness, but not necessarly 'sweet'.

You got it backwards.

 

[Jayslay]

You got it backwards.

+1. To quote Palmers book on the subject
"How to Brew" (Ch16. Pg 168 )
"....for example a 20 minute rest at 60C (140F) combined with a 40 minute rest at 70C(158F) produces a sweeter, more dextrinous beer, while switching those times at those temperatures would produce a drier, more attenuated beer from the same grain bill"

 

[tgmartin000]

You got it backwards.

Got what backwards? Longer mash - more fermentability. Shorter mash - less fermentability.

https://www.homebrewtalk.com/f36/controlling-attenuation-through-mash-times-60576/

 

[unionrdr]

In my experiences,a 1 hour mash is plenty for conversion. Longer mashes are used for pilsner malts & the like for DMS reduction if not well modified.
The Burton brewers of old,for example,did mashes of 2-3 hours to get dark fruit flavors,etc & to make them sweeter. But not more fermentable.

 

[iowabrew]

Isn't DMS more of a shorter/less vigorous boil issue?

+1 to 1 hr long mash. I've gone as short as a half hour and had full conversion.

 

[unionrdr]

Pilsner malts that aren't well modified need the extra half hour added to the mash to get rid of DMS. Well modified malts don't require this. I read up on these things on sites like midwest that sell both.

 

[iowabrew]

From Palmer:

Dimethyl Sulfides (DMS)/ Cooked Vegetable Flavors
Like diacetyl in ales, DMS is common in many light lagers and is considered to be part of the character. DMS is produced in the wort during the boil by the reduction of another compound, S-methyl-methionine (SMM), which is itself produced during malting. When a malt is roasted or toasted, the SMM is reduced beforehand and does not manifest as DMS in the wort, which explains why it is more prevalent in pale lagers. In other styles, DMS is a common off-flavor, and can be caused by poor brewing practices or bacterial infections.

DMS is continuously produced in the wort while it is hot and is usually removed by vaporization during the boil. If the wort is cooled slowly these compounds will not be removed from the wort and will dissolve back in. Thus it is important to not completely cover the brewpot during the boil or allow condensate to drip back into the pot from the lid. The wort should also be cooled quickly after the boil, either by immersing in an ice bath or using a wort chiller.

When caused by bacterial infection, DMS has a more rancid character, more liked cooked cabbage than corn. It is usually the result of poor sanitation. Repitching the yeast from an infected batch of beer will perpetuate the problem.

 

[iowabrew]

When undermodified malts are used, a decoction would be the way to go

BYO:

Traditionally, decoction mashing was used to get the most out of malt that was not produced to today’s levels of modification. In the past, malt was both less modified and more variable with respect to degree of modification.

 

[iowabrew]

Not looking to start a pissing match just citing some info.

 

[unionrdr]

From Palmer:

Dimethyl Sulfides (DMS)/ Cooked Vegetable Flavors
Like diacetyl in ales, DMS is common in many light lagers and is considered to be part of the character. DMS is produced in the wort during the boil by the reduction of another compound, S-methyl-methionine (SMM), which is itself produced during malting. When a malt is roasted or toasted, the SMM is reduced beforehand and does not manifest as DMS in the wort, which explains why it is more prevalent in pale lagers. In other styles, DMS is a common off-flavor, and can be caused by poor brewing practices or bacterial infections.

DMS is continuously produced in the wort while it is hot and is usually removed by vaporization during the boil. If the wort is cooled slowly these compounds will not be removed from the wort and will dissolve back in. Thus it is important to not completely cover the brewpot during the boil or allow condensate to drip back into the pot from the lid. The wort should also be cooled quickly after the boil, either by immersing in an ice bath or using a wort chiller.

When caused by bacterial infection, DMS has a more rancid character, more liked cooked cabbage than corn. It is usually the result of poor sanitation. Repitching the yeast from an infected batch of beer will perpetuate the problem.

When undermodified malts are used, a decoction would be the way to go

BYO:

Traditionally, decoction mashing was used to get the most out of malt that was not produced to today’s levels of modification. In the past, malt was both less modified and more variable with respect to degree of modification.

I understand all this & illuded to it without getting too bogged down in wordy explainations. The point being,DMS doesn't vaporize very quickly at all. So pilsner malts & other light ones that aren't well modified need more time to do so. That's what I was trying to explain. Understand what you read without one having to explain every minute detail to be believed. The basic processes for solving a problem are more usefull than a long tiatribe explaining the whole thing which may not be well understood by the reader.

 

[iowabrew]

^ yes but you are saying mashing longer is the way to remove DMS, when in fact, boiling longer is the way to remove DMS.

 

[MuddyCreek]

(Pulling up a chair!)

(Getting the Popcorn ready!)

 

[iowabrew]

(Pulling up a chair!)

(Getting the Popcorn ready!)

Ha! this won't be needed. I'm all out of intelligent info.

 

[unionrdr]

^ yes but you are saying mashing longer is the way to remove DMS, when in fact, boiling longer is the way to remove DMS.

Damn...you're right. sorry,used the wrong word. Thought boil said mash. Oopsie! Can't believe I didn't catch that. DMS does take a while to boil off. Boy,is my face red. I guess it proves that diet pepsi doesn't acheive the same effect as redneck rocket fuel.

 

[GuldTuborg]

Seriously, whose malts are undermodified anymore? You might find one or two examples, but I hardly think it's commonplace.

For a discussion of the effects of altering mash times, see here, here, and here.

Other things to consider are mash temps and whether you mash out or not. If you don't mash out, you're effectively mashing all the way to the boil, when the heat is raised there.

 

[iowabrew]

Damn...you're right. sorry,used the wrong word. Thought boil said mash. Oopsie! Can't believe I didn't catch that. DMS does take a while to boil off. Boy,is my face red. I guess it proves that diet pepsi doesn't acheive the same effect as redneck rocket fuel.

HA! MAN! No worries...now i feel like an ass for all that material citing!

We can all go about our business now

 

[unionrdr]

Seriously, whose malts are undermodified anymore? You might find one or two examples, but I hardly think it's commonplace.

For a discussion of the effects of altering mash times, see here, here, and here.

Other things to consider are mash temps and whether you mash out or not. If you don't mash out, you're effectively mashing all the way to the boil, when the heat is raised there.

I merely used the wrong term by mistake. I don't mash out,& not mashing till the boil. That's a def no-no. But if you mean by denaturing the enzymes after the mash,then that does happen after a certain temp is reached & surpassed heating to the boil.

 

[pjj2ba]

There is conversion, and then there is full conversion. The classic iodine test is a fairly crude measure of starch conversion. Once one gets a negative starch reaction, there is still more breakdown/modification that can occur. Shorter chain of sugars don't react well with iodine. These dextrins can still be acted upon by the mash enzymes.

True full conversion means there is nothing left for the enzymes to work on. Now if you mash just until you get a negative starch test, your wort will probably be less fermentable (result in a higher FG), than if you mash for additional time after that point (at the same temperature).

This difference will be more dramatic, the higher the temperature that you mash at, since at higher temps you tend to lose beta-amylase activity which does a much better job of breaking down small dextrins compared to the more heat stable alpha-amylase.

Generally is is stated that a cooler mash will result in a more fermentable wort (better beta-amylase activity), but also a longer mash can result on a more fermentable wort as well - compared to a mash that is only run until a negative starch test is given.

If the pH is correct, at 153F, one can get a negative starch test for the mash of a typical beer in just 30 min. By waiting for the common one hour time point, most of us have reached full conversion. So if you want a higher FG, one trick is to mash for a shorter time, rather than the more common option of simply mashing at a higher temp

 

[GuldTuborg]

I merely used the wrong term by mistake.

No problem, and thanks for the clarification.

I don't mash out,& not mashing till the boil. That's a def no-no. But if you mean by denaturing the enzymes after the mash,then that does happen after a certain temp is reached & surpassed heating to the boil.

Not sure what you mean by this. If you don't mash out, conversion takes place until you reach a significantly higher temp while building to the boil (and obviously not through the boil). That's what I meant to say, stated more clearly this time. So, no mash out effectively extends your mash time, or does it by very close approximation. Whether it's a no-no or not depends upon what you want out of your beer. There are many styles for which I frequently do not conduct a mash out, and I'm not the only one who does this.

 

[tgmartin000]

Seriously, whose malts are undermodified anymore? You might find one or two examples, but I hardly think it's commonplace.

For a discussion of the effects of altering mash times, see here, here, and here.

Other things to consider are mash temps and whether you mash out or not. If you don't mash out, you're effectively mashing all the way to the boil, when the heat is raised there.

But won't the sparge stop enzymatic activity? I batch sparge and get my grain bed up to 165 - 170. Isn't this almost like doing a mash out after you've lautered?

I ask because I think this is the reason all my beers overattenuate.

 

[GuldTuborg]

But won't the sparge stop enzymatic activity?

In the mash tun, if it's hot enough, yes. It won't affect what you initially lauter into the brew kettle. If you batch sparge, you're looking at the majority of the mash that's still sitting in the brew kettle, continuing to convert while you sparge. By the time the sparge wort hits the kettle, my guess is there's not enough overall heat in the kettle (in most cases) to fully set the mash (i.e., completely stop conversion). It might be worth measuring to see, though.

Also, it's good that you're measuring the grain bed temps. I think a lot of people batch sparge with 170F water, and when that hits a grainbed at 150, they're luck if the grain temp hits 160, which definitely does not halt conversion (right away, anyway). I suspect that's due to the adaptation of fly sparging temp schedules to batch sparging without the necessary corrections, but I could be wrong.

 

[unionrdr]

No problem, and thanks for the clarification.



Not sure what you mean by this. If you don't mash out, conversion takes place until you reach a significantly higher temp while building to the boil (and obviously not through the boil). That's what I meant to say, stated more clearly this time. So, no mash out effectively extends your mash time, or does it by very close approximation. Whether it's a no-no or not depends upon what you want out of your beer. There are many styles for which I frequently do not conduct a mash out, and I'm not the only one who does this.

Well,it sounded like the grains as well were being heated to boil. that would be the no-no. But the sparged wort heating to a boil would kill any enzymes left in the wort.

 

[pjj2ba]

But won't the sparge stop enzymatic activity? I batch sparge and get my grain bed up to 165 - 170. Isn't this almost like doing a mash out after you've lautered?

I ask because I think this is the reason all my beers overattenuate.

Enzyme activity does not simply turn off once you hit a certain temperature. It takes a while, even at 170, for the amylases to be fully denatured and lose activity. This very well could explain why your beers are over-attenuating. Try shortening your mash times (or raise your mash temp)

 

[GuldTuborg]

Well,it sounded like the grains as well were being heated to boil. that would be the no-no. But the sparged wort heating to a boil would kill any enzymes left in the wort.

Oh, no, didn't mean suggest anyone boil grains in the kettle. That's definitely not common practice.

Part of me wonders, though, what effect it would have for some beers. In that, we assume it's bad practice, but what's the essential difference between boiling grains in the kettle and decoction mashing? Duration of boil? Presence of hops? Changes in pH after addition of sparge water? Why is one bad but the other good?

 

[pjj2ba]

Oh, no, didn't mean suggest anyone boil grains in the kettle. That's definitely not common practice.

Part of me wonders, though, what effect it would have for some beers. In that, we assume it's bad practice, but what's the essential difference between boiling grains in the kettle and decoction mashing? Duration of boil? Presence of hops? Changes in pH after addition of sparge water? Why is one bad but the other good?

It is mostly a matter of proper pH, and not having a lot of roasted malts in the grain bill. As long as the pH is in the proper range (~5.5) you are fine.

I have boiled two full mashes, one intentionally, and one accidently. The accidently one turned out fantastic! I do step mashes, and forgot to turn off the heat as I raised the mash to is final saccharification step and got distracted and came back to a boiling mash. The flavor was great, but it had a terrible starch haze that would not clear.

 

[stz]

I tend to try and ignore the 'temperature a causes b so temperature c causes d and you can lean towards one or another' because there are many other factors involved in determining the 'profile' of the wort and so its fermentability. I try to think in terms of 'beta amylase bias or alpha amylase bias'.

Like ratio of water to grain. Like pH. Like length of time. Like temperature. Like steps. Because of this, unless you really want to understand it all, just sort of lean your practice towards the desired profile with a rough understanding of how the factors modify it. For example, a short mash at high temperatures is likely to result in more unfermentable sugars and a higher final gravity. But so would a long mash at high temperatures with a higher ratio of water to grain.

Also so many yeast strains attenuate at different degrees and handle different sugars. It is complex, I try to just take a stab at it based upon the overall vision of what I'm trying to create.