Stepped Mash Infusion

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O-beer-wan-kenobi

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I'm about to do my first stepped mash infusion. I have only just started reading up on the various temperature, their durations and their effects.
Below is what I am planning to do and just want to get some feed back and if there are any changes I should make to get a better result?

Batch Size (fermenter): 21.00 l

Boil Time: 90 Minutes

Ingredients:

4.00 kg Pilsner (2 Row) 80.0 %
0.75 kg Corn, Flaked 15.0 %
0.25 kg Cara-Pils/Dextrine 5.0 %

18 g Perle [8%] @60 min
10 g Cascade [5.5%] @ Boil 10.0 min
10 g Cascade [5.5%] @ Flame out
IBU 20

(Wyeast Labs #2007)


Protein Rest - Add 8.75 l of water at 56.0 C 50.0 C 15 min
Protein Rest - Add 3.25 l of water at 92.8 C 60.0 C 60 min
Saccharification - Add 3.00 l of water at 99.4 C 67.0 C 15 min
Mash Out Add - 8.50 l of water at 93.9 C 76.0 C 5 min
 
60 is a beta amylase rest rather than a protein rest (although there wiill still be crossover of enzyme activity throughout various ranges).

I am a fan of targeting both beta and alpha amylase during a mash but if you mash at 60 for 60 minutes, I doubt there will be much that the 67 rest will achieve.

In my view, shorten the lower rest - especially if it's as low as 60 and lenghten the higher rest. I'd also bump it up to 68 at least.

It does depend a bit on what you are aiming for: I like malty, full bodied beer that attenuates properly most of the time. My beers that are stepped at 62/63 fro 10-15 minutes and then mashed at 68-69 will always attenuate as well as any single infusion beers - usually 1010-1012, (yeast dependent, etc).

I even make saisons the same way but extend the low rest to 20 minutes and drop the higher one down. 1006-1008 with 3711 at ambient temps in summer.
 
60 is a beta amylase rest rather than a protein rest (although there wiill still be crossover of enzyme activity throughout various ranges).

I am a fan of targeting both beta and alpha amylase during a mash but if you mash at 60 for 60 minutes, I doubt there will be much that the 67 rest will achieve.

In my view, shorten the lower rest - especially if it's as low as 60 and lenghten the higher rest. I'd also bump it up to 68 at least.

It does depend a bit on what you are aiming for: I like malty, full bodied beer that attenuates properly most of the time. My beers that are stepped at 62/63 fro 10-15 minutes and then mashed at 68-69 will always attenuate as well as any single infusion beers - usually 1010-1012, (yeast dependent, etc).

I even make saisons the same way but extend the low rest to 20 minutes and drop the higher one down. 1006-1008 with 3711 at ambient temps in summer.

Thanks manticle, I read that the longer you leave the mash at 60 the drier the beer, which is I guess is why I went for 60 min. Although I do like a malty beer, this first go at a step infusion mash is going to be a bit of a learning exercise.

How long do you rest at 68-69? Do you have any comments on the initial infusion at 50 deg C, I have read a lot of people go for something lower at 40 - 42?
 
I'm about to do my first stepped mash infusion. I have only just started reading up on the various temperature, their durations and their effects.
Below is what I am planning to do and just want to get some feed back and if there are any changes I should make to get a better result?

Batch Size (fermenter): 21.00 l

Boil Time: 90 Minutes

Ingredients:

4.00 kg Pilsner (2 Row) 80.0 %
0.75 kg Corn, Flaked 15.0 %
0.25 kg Cara-Pils/Dextrine 5.0 %

18 g Perle [8%] @60 min
10 g Cascade [5.5%] @ Boil 10.0 min
10 g Cascade [5.5%] @ Flame out
IBU 20

(Wyeast Labs #2007)


Protein Rest - Add 8.75 l of water at 56.0 C 50.0 C 15 min
Protein Rest - Add 3.25 l of water at 92.8 C 60.0 C 60 min
Saccharification - Add 3.00 l of water at 99.4 C 67.0 C 15 min
Mash Out Add - 8.50 l of water at 93.9 C 76.0 C 5 min


the best thing to do is have a good read of:
http://www.byo.com/stories/techniques/arti...of-step-mashing

I found it the best information for step mashing.
 
Thanks manticle, I read that the longer you leave the mash at 60 the drier the beer, which is I guess is why I went for 60 min. Although I do like a malty beer, this first go at a step infusion mash is going to be a bit of a learning exercise.

How long do you rest at 68-69? Do you have any comments on the initial infusion at 50 deg C, I have read a lot of people go for something lower at 40 - 42?


beta amylase (more active at the lower temp - 60 degrees) will chop starches up into shorter chain sugars that are easily digested by the yeast, leading to a lower bodied, well attenuated beer (eg dry).

Alpha amylase (more active at the higher temp) will chop up starches into dextrins or longer chain sugars which leads to a fuller bodied, chewier beer that can attenuate less well.

By targeting both sets specifically rather than at a compromised temp (say 66) you have greater control over the end result. However, a full 60 minute mash at temps that favour beta amylase probably won't leave much for the alpha - they won't 'rebuild' the chains once they are chopped up. Yes 60 will give a dry beer but the next rest won't have anything to work with.

Typical regime for me is 62/63 for 10-20 mins depending on whether I want dry like a saison or more full bodied like a Belgian Golden or an altbier. Then I rest at the high rest for anything between 40 and 50 minutes before doing another 10 minute rest at 72 (glycoprotein for head retention)

As for the protein rest -again it depends on what you aim to achieve. I use a short, higher end protein rest at about 55 degrees for 5 minutes. Overly long protein rests are unnecessary with most modern malts and it is often said that doing one will hurt head retention. However the short rest at 55, combined with the rest at 72 will (from experience and reading) help give a stable, moussy, tight head.

42 as far as I can remember favours ferulic acid and is best used for wheat beers that favour clove. Above 45-47 favours breakdown of proteins, low 40s favours beta-glucanase activity (a good idea if using lots of gummy grain like Rye as far as I understand) and below 40 has been used to help drop mash pH.

The above is a mixture of my experience resting at various temps and my reading about temperature rests and enzyme activity, particularly from Principles of Brewing Science (ed II). In that book, Fix suggests that the acid rest (35-40) is fairly redundant as while acid forming enzymes are active between 35-40, their effect on pH is counteracted by the buffering capabilities of the mash
 
manticles advice has helped me a great deal with step mashing ( I have 2 kegs of helles on,tap, yum! ), and also braukiser.com. Google "hochkurz", a simple step mash that lots of big german breweries use.
 
What would be the effect of reversing the mash schedule? What happens to a mash that is 68c for 40 minutes and at 62c for 20 minutes? Can the beta amylase continue to further break down what alpha amylase has already?

I have searched for this info, but most sources simply talk about the ranges of beta and alpha amylase and always list it in ascending order (as this is more practical on the way to mash out and boil presumably).

I ask out of pure curiosity...
 
Tony Wheeler, who wrote a great, fairly well known article on simplifying water chemistry (among other things) used to step mas exactly that way and as far as I know it should work absolutely fine.

The main reason I step up is because it's easier for me to heat than it is to cool - I imagine that's pretty widespread but theoretically you could step down if you have the means (cold water infusion would be one way).
 
Obviously the reason we go up, as opposed to down, is that at the end of the process you need to go up again to achieve the boil. I doubt if any commercial brewery would go down, for energy reasons. I only go down in circumstances that are off topic for this thread.
 
Besides energy/time required arguments..if you mashed downward in temp, wouldn't the first infusion kill off or denature the enzymes you would then try and get to at cooler temps?
 
Probably at over 70 degrees the Beta Amylase may well be denatured - if you were going downwards there may be a case for adding some more base malt to replenish the Beta. Might work if you are doing an overnight mash. Can't see the point personally.
 
I think you will find that beta amylase denatures lower than 70, I have been lead to believe it is closer to 65 when it starts unravelling.

However, I totally agree with Manticle on his mash regime and I do pretty much the same thing except when I am trying to copy a low-carb beer like Pure Blonde for example (something which I've pretty well nailed) and mash at 63 for 90 minutes.

Steve
 
The alpha amylase will be active at ~63c-64c and will be creating more branch points for the beta amylase to form maltose from. Which probably helps increase wort fermentability.

As you go lower from that, alpha's activity drops off.
 
Also, when adding boiling water as you do in your saccharification rest I'd adjust the water temperature in your brewing software to about 96.5 degrees... you'll find that's a little more accurate.
 
Hmmm so not totally cut and dried? Anyone with sources to point me towards?

I am not asking as a possible/potetnial way to mash or anything, just curious.

Joe Brewer mashes in at 68c in a shitty old esky and comes back in 90minutes after mowing the lawns and the mash is 61c (this is hypothetical, don't bombard Joe with suggestions for a new mash tun hahaha), will Joe's mash have a heap of beta amylase action once under say 64c or not? Or has the initial temp created a circumstance where beta amylase will have a hard time of it?
 
Beta amylase won't denature at 68 degrees. It's just not optimised.
Lecterfan - start with George Fix - principles of brewing science, easily and cheaply available from book depository. Last few pages of chapter 1, 2nd edition.
Be aware that beta & alpha amylase are oddly and incorrectly reversed within.
 
There's been so much focus on mash scheduling that a few important things have been left unsaid... Exclusive infusion mashing is a technique that can quickly and easily go wrong - many learn thus by experience, including me. If your strike in water temp or calculation is out, each subsequent volume and temp will become more and more out too. So here's a couple of tips:

Stir you HLT water to ensure consistent temp prior to filling for strike.

Preheat your MLT with a kettle of boiled water, as the material temp is usually way colder than anticipated and also tends to absorb more heat than calculated.

Once your strike water is in the MLT, stir it and double check its temp - you aren't under pressure until you add the grain, so be certain first.

Keep a boiled kettle and a pail of cold water at the ready for emergency adjustments.

Try to relax and don't expect things to go to plan, but be prepared to take notes so that you can iron out any miscalculations next time.

Good luck and have fun!
 
Hmmm so not totally cut and dried? Anyone with sources to point me towards?

I am not asking as a possible/potetnial way to mash or anything, just curious.

Joe Brewer mashes in at 68c in a shitty old esky and comes back in 90minutes after mowing the lawns and the mash is 61c (this is hypothetical, don't bombard Joe with suggestions for a new mash tun hahaha), will Joe's mash have a heap of beta amylase action once under say 64c or not? Or has the initial temp created a circumstance where beta amylase will have a hard time of it?

Probably not but you could have some. How much is guesswork. It depends on the time it's been at or close to 68. If the temperature fell pretty quickly, I would say you would have quite a bit of active BA.

There are a lot of factors. For example, it doesn't matter how well you stir your mash you will have hot and cold spots and the variation can be quite extensive. Commercial breweries have constant mash agitation to address this. It's not practical or necessary for home brewing on such a small scale, getting 90% efficiency is not our goal.

At the end of the day, it is not a super important. You will not see a great difference - if any at all - between a single infusion mash and a stepped mash. If you make a beer starting at 68C and it drops to 61 over 90 minutes that is perfectly okay, you will make great beer with good efficiency. If you do a step mash you will end up with a result that is so close to the single infusion, you'll wonder why you done it. If you're making a robust flavoured beer you won't tell any difference and a very light lager a slight difference.

That's my take on it anyway at homebrewing level. Not everything is scalable so scaling big brewery techniques to a home brewing level usually does not work although the principals remain the same

Steve
 
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