Mashing technique: infusion, step, decoction?

[jason.koehler]

Hey gang,

I'm hoping to soon be back in the brewing game after a 3 year absence as we're currently having some demolition done on one of the upper floors of my pub to make room for a small brewery on site. I was hoping that you all can answer a question...

I'm curious as to how others are mashing, particularly those with small systems, especially those under 3 bbls.

Thanks!

[BigWilley]

Someone will have to explain to me why you would do anything other than a single step mash with a start up? Decotion? Why? With todays highly modified malts why bother? I can see for a specialty brew but why for your regular lineup? Simplicity is best if you are trying to start from scratch.

[jason.koehler]

Thanks for the quick input! I went to bed and woke up with a lot of responses! I remember now why I've always loved this forum community!

My entire professional brewing experience was spent at one brewery, and we did only step mashing. In fact, even as a homebrewer I haven't really ever done an infusion mash! In designing our brewhouse and process at this new venture, I ran into an unexpected wall in that my partner wants to design a system around single infusion because that's his homebrew background and for ease of process/simplicity.

His idea is to use an on-demand water system for strike water, mash in the lauter then recirc to clear before pumping to the kettle. My idea is similar, using the on-demand water for strike temperature, but I'd rather mash in the kettle for better temp control (direct fire) and step mashing then move to the lauter for vorlauf, then back to the kettle for the boil.

I don't mind having an infusion system so much, as I know many people make great beer with that technique, but I want some flexibility to do step mashing in the kettle when I want to. Decoction is likely easier mashing in the lauter and pumping wort to the kettle, but I don't have any plans to do that at this time.

I know this could be solved by using a second heating element in the lauter, that way we'd have the ability to do both styles, but we're planning on the lauter out being on the bottom, so it would have to be electric on that side...an idea I'm not crazy about.

[dick murton]

Have to say that especially for a small system such as you are proposing, I would also stick to as simple as possible, and mash in the mash tun, leave to stand and run straight off.

I don't understand why you want to vorlauf on simple systems like this as I can only imagine it helping to blind the bed, and if the grist is well enough modified, and fairly coarsely ground, and the plate slots / holes are not too large then you don't get much flour being generated or pulled through. Are you intending putting rakes in the lauter ? And if you are, but the malt is well modified and reasonably coarse grind, why ? I am genuinely intrigued.

If the mash tun is filled with the right amount of hot water and you then simply pour in the grist and stir in, you shouldn't get much rubbish dropping through into the kettle.

Why not use the kettle to heat the mash liquor and sparge liquor up, to say 85 C, transfer what you need to the mash tun, and transfer the rest to an inulated holding tank? A bit of a fiddle until you get into the rythym of it, but worked pretty well with a much larger system than proposed.

[Ted Briggs]

"His idea is to use an on-demand water system for strike water, mash in the lauter then recirc to clear before pumping to the kettle." Would work great for small system- might want 2 units in series. Id go with this, it would provide good hot water for all brewery uses independent of brewhouse operations.
"I'd rather mash in the kettle for better temp control (direct fire)" I think you would see allot of scorching of the grain w direct fire even with good mixing.
"and step mashing then move to the lauter for vorlauf, then back to the kettle for the boil." You would need a expensive pump on a vfd, preferably reversible, for this to work because your pumping solids. Also larger diameter piping. it can be done though- I had a DME system like this
" but I want some flexibility to do step mashing in the kettle when I want to." Why? Are you going to make allot of wheat/rye beers? Alot of dry lagers? -the process determines the product and the product determines the process...

[jason.koehler]

Dick, the mash tun won′t have rakes but we are considering a side mounted stand mixer to ensure a thoroughly mixed mash, as well as to take a little work off our aching bones.

This 225 liter brewery will be tucked into about 16 square meters, with not a lot of room to spare, and is on the 4th floor of a building with no elevator, so with the fermentation side being there too, space is at a real premium - thus the need for a wall mounted hot liquor source. Fortunately it has a dumbwaiter for malt and kegs.

I′m not anticipating a coarse grind, as we′ll need every drop of efficiency we can get out of this system in order to meet the minimum production requirement to get a permanant license, but we′ll be having our own false bottom punched, so we can make sure it will be suitable for recycling. For a fairly fine grind, what kind of slot width would you suggest?

Ted, they offer commercial on demand systems here for up to 75-80c temps, so one should do. I heard of another small brewery using two in tandem like you suggested as well, but I heard they were home models. The one at my house can do about 25-30 liters per minute at up to 50c...I love these things!

I am probably going to have one wit or saison and a Cali Common in the works most of the time, thus the want for step mashing from the get‐go. I′m finding it doesn′t take a lot extra to set up a system capable of both.

[dick murton]

From memory, the slots that are milled out / welded up to give in bigger systems such as used by Steinecker and Huppman are 0.7 mm at their narrow point. Every system I have seen with drilled plates rather than slotted plates has much bigger holes, but nothing like the total free surface area of milled or wedge wire plates. The drilled plates have all (to date) had a cone drilled out on the underside though to reduce risk of blockage, rather than simple drilled holes.

The more holes / slotted area the better, providing the plates hold together, especially if you have to stand on them to grains out.

[jason.koehler]

Thanks Dick,

So the holes on the bottom are wider than the top then? That's good to know...and interesting. Getting something milled like that might be expensive though.

For a 80 cm wide 60 cm high kettle, would you have any suggestions for gap/hole size for slotted or milled?

[gitchegumee]

Standard V-wire screen is 0.020" gap.

[theBrewMeister]

heat your water, overnight, in the kettle. This drives out any chlorine and whatever. Mash-in, single infusion. Heat your sparge water in the kettle, send thru the heat exchanger into the clean fermenter you'll be using for this brew - this sanitizes the HE and the FV. Send sparge from FV to mash tun - this sanitizes any remaining hoses needed later. Vorlauf just long enough to set the bed and send to kettle. Simple as that. Dont over complicate your day - you'll be looking to do this sooner or later anyway.

[GeorgeJ]

Jason,

i've always been astonished at breweries who bother step mashing with good maris otter.. and decoction is fun, but you also have a business to be running with your time - it's not just a hobby that gives you a few hours away from 'er indoors.

however, given that you guys are gonna be going for your happoshu license, you are gonna have to add some unmalted adjuncts. (that's my understand of how happoshu licensing works, anyway).

Although your enzyme potential with well modified malts is fine, you might want to give yourself some step rests so help with proteins that you will find in i.e. unmalted wheat, or rye.

Let me and Scott know if you guys need and help or have any questions.
I personally am eager to help the scene locally!