Mashing in Decreasing Temp Steps

[ohad]

Hi All
I always use a single infusion mash.
I've done some reading about step mashing, and I have one question.

Is there any mashing scheme where the steps go from higher temp to lower one?

the way I understand the process, as you go higher in temp the higher conversion of starch into dextrins you get. the lower you go, the better the conversion of dextrin into maltose you get.
If this is correct, wouldn't a mash that starts, lets say, at 157ºF for 40 minutes, and then another step at 147ºF for 60 minutes (or so) give me the highest conversion? (If I want a very dry beer)

 

[Jack]

On the contrary, mashing in at 157 for 40 minutes would result in a relatively unfermentable wort even if you drop the temperature later on. Higher temperatures yield less fermentability (more sweet) than lower temperatures (drier).

I've never heard of mashing schemes in which you decrease the temperature. Normally, if I do steps I do them at 103, 122 (protein), and then the main sacchrification rest temperature (145-160, depending on how fermentable I want the wort to be). I think it might be unusal to have multiple steps in the sacchrification temperature range.

 

[Passload]

In step Mashing you start out at the lower temps. If you want a lighter body beer you could do something like this.

Protein Rest Add 12.50 qt of water at 129.3 F122.0 F30 min Saccharification Heat to 150.0 F over 15 min150.0 F 75 min Mash Out Heat to 168.0 F over 10 min 168.0 F 10 min​

Or

Protein Rest Add 9.00 qt of water at 132.1 F122.0 F30 min Saccrification Add 8.00 qt of water at 187.9 F 150.0 F 30 min Mash Out Add 8.00 qt of water at 210.3 F 168.0 F 10 min​

These are not hard set rules.

 

[Kaiser]

Is there any mashing scheme where the steps go from higher temp to lower one?

This is a common conclusion when seeing the different temps for the enzymes. But it doesn't work this way because once you get above the optimum temp for an enzyme you start denaturing it. So mashing high to get the dextrines will kill the beta amylase that you needed later for the maltose.

This going back in temp would only work when you add fresh malt to add fresh enzymes or in decoction mashing where a part of the mash is kept at a lower temp and will provide enzymes.

To get a very fermentable wort, you need to mash at a low temp (148-149F) and may also hold that mash for a longer time (90 min) to compensate for ther slower a-amylase activity.

Kai

 

[ohad]

This is a common conclusion when seeing the different temps for the enzymes. But it doesn't work this way because once you get above the optimum temp for an enzyme you start denaturing it. So mashing high to get the dextrines will kill the beta amylase that you needed later for the maltose

Thats the answer I was looking for! thanks a lot!
Are you sure about this?

(BTW, I know what I need to do in order to get a highly fermentable wort, I was just wondering if there is any non-traditional way of doing it)

 

[david_42]

40 minutes at 157F would destroy all (or nearly all) of the beta amylase.

 

[Kaiser]

Are you sure about this?

Yes. It may work to some extend (lowering the temp to get more beta amylase activity) but I have not seen it being used in commercial mashing (as far as I know) even though some of them are very interested in highly fermentable wort (i.e. light beers)

I was just wondering if there is any non-traditional way of doing it

A non traditional way would be the mashing in at 2 qt/lb at 100F. After occasional stirring and 10 – 20 min remove the liquid that’s on top (about 50%) and place it in a cooler. Now heat the mash to 160 and rest there until fully converted. Bring it to a boil and then slowly return the mash to the cooler to reach 140F and rest it there for about 60 min. Then decoct for mash-out. This should give you very fermentable wort. The first step gelatinizes and converts almost all the starch to small dextrines. The second step, with the help from the enzymes (mainly beta amylase and limit dextrinase) that were put aside in the liquid, will create lots of maltose and glucose. You are able to rest at such a low sacc temp b/c you already gelatinized the starches. I plan to use this mash for a strong blonde Doppelbock in the future. I’m curious if it does what I expect it to do.

Kai

 

[Stevorino]

Go low to high.

 

[malkore]

Remember that those enzymes have to 'work' on converting the starch to sugars, and the amount of time you let them work at a temperature is why it affects fermentability and body.

 

[ohad]

I like you idea, Kaiser.
so what about this: first rest 154, second at 147.
at 154 you get good functionality out of both enzymes, and then a better conversion into maltose at 147.

 

[wildwest450]

(If I want a very dry beer)

If you want a dry beer mash @ 150F for 75min. As simple as that.

 

[Kai]

Yes. It may work to some extend (lowering the temp to get more beta amylase activity) but I have not seen it being used in commercial mashing (as far as I know) even though some of them are very interested in highly fermentable wort (i.e. light beers)



A non traditional way would be the mashing in at 2 qt/lb at 100F. After occasional stirring and 10 – 20 min remove the liquid that’s on top (about 50%) and place it in a cooler. Now heat the mash to 160 and rest there until fully converted. Bring it to a boil and then slowly return the mash to the cooler to reach 140F and rest it there for about 60 min. Then decoct for mash-out. This should give you very fermentable wort. The first step gelatinizes and converts almost all the starch to small dextrines. The second step, with the help from the enzymes (mainly beta amylase and limit dextrinase) that were put aside in the liquid, will create lots of maltose and glucose. You are able to rest at such a low sacc temp b/c you already gelatinized the starches. I plan to use this mash for a strong blonde Doppelbock in the future. I’m curious if it does what I expect it to do.

Kai

That looks like a very interesting mash procedure. My only point of comparison for this is the turbid mash procedure, where the liquid drawn off is boiled (in order to get poor conversion and dextrines). The description of that liquid as 'turbid', though, makes me think that there is a high proportion of unconverted starches in the fluid. Would beta amylase alone (because that's all you'd really have going at that temperature) take care of those starches satisfactorily? I suppose limit dextrinase would do some debranching while the rest of the mash was boiling, which could help it . . .

I'm intrigued. Let me know how this mash schedule works for you. I might use it for Saisons and other bone-dry beers.

-Kai

 

[Kaiser]

Would beta amylase alone (because that's all you'd really have going at that temperature) take care of those starches satisfactorily?

If most of the starch is in the deoction to begin with, it will be converted to dextrines before the boil. The boil will release some starches, but there will also be enough a-amylase activity at 140 to take care of them. If not, there is a mash-out step that supercharges the a-amylase and takes care of all the remaining starch and long glucose chains.

Kai

 

[ohad]

40 minutes at 157F would destroy all (or nearly all) of the beta amylase.

OK... so what if that first step would be at 154.5 and the second at 147 ?

I can't understand how this can denaturate the enzymes, since they work well in this temp.

 

[EvilTOJ]

The heat destroys the alpha enzymes, which is another name for denaturing them. Even two degrees does make a difference. You keep asking about how to go from high mash temp to low mash temps, and it doesn't work that way. You HAVE to go from low to high.

Kaiser is talking about decoction, which is mashing in a completely different way than just step infusions. He did a very good video series on decoction mashing, it's a sticky.