Biab step mash

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rossbaker

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Hi guys, I'm looking to try this Bavarian what beer from the ahb data base :

https://aussiehomebrewer.com/threads/recipedb-schneider-weisse-style.20713/

It says to do a 50 deg infusion for 20 minutes then mash at 63 deg for an hour.

My questions are :

Does this still work if doing a full volume biab mash? How would you go about it?

How does the 50 deg rest affect the beer? What would I be missing if I skipped it and just did the 63 deg mash?
 
A Multi step mash is called a 'decoction mash'. Thats the term you need to go researching with.

A rest at 50deg is the sweet spot for the enzyme beta-glucanase, which breaks down beta-glucans.

It's a common step when using large amounts of unmodified grains, or grains rich in beta-glucans, such as the pale wheat in the recipe you have linked too.

edit

Yes it will work doing BIAB.

You can heat the water to a few degrees above 50, dough in, rest, then ramp the temp up to 64 or so and rest, followed by mash out, heating up to 78 and resting.
 
Last edited:
Two points here:

No, a multi step mash is not usually a decoction mash. That refers to the special case of a stepped mash where grain is removed from the mash, brought to the boil and then returned to the mash tun to raise the temperature. This is done repeatedly until the desired end temperature is reached. You can certainly do this with BIAB but it's messy and time consuming.

Whilst a decoction mash is a typeo of multi step mash, nowadays most multi step mashes are not decoction mashes.

Secondly, what equipment are you using for BIAB? If it's using an element to raise the temperature between mashes - as in an urn - then if the element is in contact with the mash then you are likely to scorch the element badly trying to raise from 50 degrees onwards because, at that low temperature, there will be heaps of flour that hasn't entered the temperature zone where it can be converted, so can coat the element and burn.

You can avoid this by starting with a thicker mash at 50 degrees then raise to 63 by adding boiling water until you get there and then only switch on the power when some conversion has started. After that you can raise through the other steps to mashout, whilst keeping the bag away from the heat source and stirring the mash now and again.

With modern well modified malts you probably wouldn't notice much difference by starting at low 60s, which is a typical German Hochkurz mash as used by nearly all modern German breweries.

Heaps of information about the various German infusion mash schedules at Braukaiser.
 
A Multi step mash is called a 'decoction mash'. Thats the term you need to go researching with.

A rest at 50deg is the sweet spot for the enzyme beta-glucanase, which breaks down beta-glucans.

It's a common step when using large amounts of unmodified grains, or grains rich in beta-glucans, such as the pale wheat in the recipe you have linked too.

edit

Yes it will work doing BIAB.

You can heat the water to a few degrees above 50, dough in, rest, then ramp the temp up to 64 or so and rest, followed by mash out, heating up to 78 and resting.

Thanks for the reply lionman. That is pretty much the method I was picturing. Great to have confirmed this.
 
Two points here:

No, a multi step mash is not usually a decoction mash. That refers to the special case of a stepped mash where grain is removed from the mash, brought to the boil and then returned to the mash tun to raise the temperature. This is done repeatedly until the desired end temperature is reached. You can certainly do this with BIAB but it's messy and time consuming.

Whilst a decoction mash is a typeo of multi step mash, nowadays most multi step mashes are not decoction mashes.

Secondly, what equipment are you using for BIAB? If it's using an element to raise the temperature between mashes - as in an urn - then if the element is in contact with the mash then you are likely to scorch the element badly trying to raise from 50 degrees onwards because, at that low temperature, there will be heaps of flour that hasn't entered the temperature zone where it can be converted, so can coat the element and burn.

You can avoid this by starting with a thicker mash at 50 degrees then raise to 63 by adding boiling water until you get there and then only switch on the power when some conversion has started. After that you can raise through the other steps to mashout, whilst keeping the bag away from the heat source and stirring the mash now and again.

With modern well modified malts you probably wouldn't notice much difference by starting at low 60s, which is a typical German Hochkurz mash as used by nearly all modern German breweries.

Heaps of information about the various German infusion mash schedules at Braukaiser.

Thanks Bribie, I read a post of yours asking about decoction mashes. Sounds complicated, but worth having a go of eventually.

My setup is a gas fired keggle. Would scorching still be an issue when raising from 50 deg or would this be fine if it is gently heated?

Would be keen to get my head around how this step actually changes the beer. Will have to keep reading.
 
I tried a step mash in my urn once. Never bloody doing that shit again, had the exact problem Bribie described with the floury shit coating the element; it caused it to cut in and out and was just a complete pain in the arse. The fuckin beer wasn't even that nice, I've done the same recipe numerous times since just starting at 63, up to 72 then mash out, pretty much a Hochkurz mash, and it's been a thousand times better.

A gas fired keggle might be different though as you're not dealing with an element.
 
I'd give it a go in the keggle. The worst that can happen is some elbow grease afterwards if you get some scorching on the bottom.

On the other hand a keggle setup would be great for the boiling water addition method.
 
I've done a stepped mash 4 of the 5 times I've ever brewed! jejeje (I'm not trying to mock anyone, yes, I'm a total rookie). The point of doing BIAB (if I understood it right) is to use minimal equipment in the simplest way for making good beer from scratch (all-grain).

What I've read in every guide/forum/article about BIAB is to use the same kettle for everything except fermentation, obviously. If you are doing a stepped mash you have to be careful not to burn your bag, that is, the part outside the kettle (use clothespegs, papelclips, or any kind of clamp) as well as te bottom part of the bag inside the kettle. For that I use the steaming part of my express cooker upside down, the idea is to have something inside the kettle for avoiding the bag to be in direct contact with the bottom of the kettle. The metal accesory of a microwave-grill ? whatever!
In between steps, I simply wrap the kettle with something to avoid loosing heat (I use some insulated bags from the supermarket).

What I've experienced lately is that my efficiency has increased by using the paddle all the time while rasing from one step to the next one.

I'm sure you have much more experience than me and you already knew everything I told you, but... trying to help jejeje
 
Two good bits of BIAB kit are:
curved roasting rack.jpg


From a kitchen shop
and

From Big W, a cheap doonah secured round the urn with a couple of bungee cords.

Their doonahs are light as a feather, fabulous insulators and start around $9 which is amazing. Also washable after a bit of wort staining.
 
You told me about the Big W doonah! $ for $ still the single best investment I've made! Even in winter I can lag my urn in the garage (8C ambient) and only lose1.5- 2C over 60 mins. In summer I lose approx .5C over 60 mins. That's accurate enough for me!
 
I do step mash as I know it quite often biab.
I have a false bottom so bag cant be it direct contact with gas heat
I monitor the temp rigorously turn the gas of 1.5 deg from temp wanted as heat rises and continuously stir till rest period temp is reached It seems to work but it is hard work gotta be on it
my 2 cents
 
That's great guys. I'll use the same woollen blanket I use for mashing during the 50 Deg rest. It sounds like raising from rest temps to mash temps will be the same process as raising from mash to mash out temp.

I've recently acquired a high quality the thermometer (lavatools not thermapen) so I'm feeling way more confident about hitting the correct temp.

Sorry to bang on about the same question, but can anyone point me in the right direction r.e learning about what this rest/decoction does in terms of altering the finished beer?
 
As bribie said - this is not a decoction mash. Unless you remove a portion of the grain and boil, then return to the main mash and raise temp that way, it's just a step mash.

A mash at 50 will degrade some of your shorter length proteins.

For a reasonable summary, read this: https://byo.com/mead/item/1497-the-science-of-step-mashing and also Bribie's suggested braukaiser
 
Thanks for clearing that up guys. I was under the impression that decoction was the most common way this was done, traditionally at least.

Can't you remove some wort, boil that in the stove (or burner) and return it to the mash in a sort of sudo decoction? You would need a reasonably sized pot, around 20L minimum probably.

You can heat the mash in biab as long as your bag is seperated from the base of the pot or element. This is how single vessel breweries like robobrew or Grainfather work. It helps if you can recirculate while it's heating either with a pump or manually by draining to a bucket and pourimg the wort back into the mash. This will help reduce scorching etc.
 
most important keep bag away from heat source I burnt the arse outta two good bags and lost the contents
 
The "original" recipe is quite a bit more complex, however I suspect the 50oC rest and the step up to 63oC could best be achieved by mashing in heavy (say 2-2.5:1) followed by a hot water addition to achieve the step (lots of online calculators out there if you cant do the maths), with a full volume BIAB there should be plenty of room for another step to mash out temps.
I question the need for protein rests with modern malts, but in this case I think I would stick with known process.
Before you start to edit the procedure, there is a very good discussion on BYO Weissbier, worth reading and your yeast choice is critical, get the right one.
If you can find a copy of the BYO 250 Recipe magazine it gives a very good step by step specifically for Schneider
Schnider.jpg

Mark
 
Thanks for clearing that up guys. I was under the impression that decoction was the most common way this was done, traditionally at least.

Can't you remove some wort, boil that in the stove (or burner) and return it to the mash in a sort of sudo decoction? You would need a reasonably sized pot, around 20L minimum probably.

You can heat the mash in biab as long as your bag is seperated from the base of the pot or element. This is how single vessel breweries like robobrew or Grainfather work. It helps if you can recirculate while it's heating either with a pump or manually by draining to a bucket and pourimg the wort back into the mash. This will help reduce scorching etc.
Good idea lion man, I could use my old big w 19l pot for that.

I don't have a pump but I often manually recirculate when mashing out. Hoping to get a pump soon though to use with plate chiller.
 
The "original" recipe is quite a bit more complex, however I suspect the 50oC rest and the step up to 63oC could best be achieved by mashing in heavy (say 2-2.5:1) followed by a hot water addition to achieve the step (lots of online calculators out there if you cant do the maths), with a full volume BIAB there should be plenty of room for another step to mash out temps.
I question the need for protein rests with modern malts, but in this case I think I would stick with known process.
Before you start to edit the procedure, there is a very good discussion on BYO Weissbier, worth reading and your yeast choice is critical, get the right one.
If you can find a copy of the BYO 250 Recipe magazine it gives a very good step by step specifically for Schneider
View attachment 107960
Mark
Excellent article, thanks Mark. I had never heard of using wort for the last secondary fermentation. Interesting that the article suggests doughing in at 37 deg, where the recipe I linked to suggested 50 drg. I'll try 37 this time and see how I go. Will add hot water to get up to full volume after the rest then just make sure the bag is off the base if I need to use the burner to heat it further.

I have read that decoction and step mashes are only necessary if using certain malts. Does anyone know if the grains in my recipe warrant this?
(wheat, Vienna, pilsner, caramunich 1)
I'm happy to keep it simple and just mash in at 63 if it makes no difference...

Final question, I'm using wlp351 (Bavarian wheat). Does this need a starter?
 
There is a wide gap between 'necessary' and 'makes no difference'.

It is certainly not necessary to step mash in order to make beer, using the malts listed.
 
37-38oC is the temperature where you get the most enzymes into solution (called Dissolution), in a beer where you are really trying to get the most out of all the enzymes it can be a benefit, especially when you are taking some of the malt out to do a decoction (as the enzymes get killed during the decoction, so what stays in the wort survives).
With modern malt I would probably wind back or just ramp through (depending on equipment) the protein rest (50oCish). Braukaiser covers using specie very thoroughly, well worth reading.
Agree with manticle on the Necessary V No Difference, decoction does things to beer that nothing can fake.
Mark
 
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