Underletting

[barry44]

I like the sound of this. I use my boiler to heat my strike water, treating it as necessary.

I also count my dead space as part of my strike volume to ensure that I have had added the correct amount of salts.

Usually this isn't a problem as I over heat the strike water, fill the mash tun from the tap and pick up the boiler and pour in when feasible.

I assume I can underlet until the boiler has drained to the dead space and then pour in as necessary?

I use 2.5l per kg in my mash.

Cheers,

Barry

[far9410]

I. Always add water to mash tun allow to stand to warm up the tun, then check adjust to strike temp then dough in. If I change to under letting how do you allow for temp drop?

[Horatio]

I. Always add water to mash tun allow to stand to warm up the tun, then check adjust to strike temp then dough in. If I change to under letting how do you allow for temp drop?

I preheat my mash tun first (thermo pot). I add water at around 75c for 15 minutes then drain before adding the grist. I keep the grain bill at room temp too. I then underlet at 74c to get a mash temp of 67c. It works for me and if I need a higher lower mash temp I just raise or lower the HLT water temp by the extra amount of degrees; eg, for 68c mash I get the HLT to 75c or for a 65c mash it goes in at 72c.

[GrowlingDogBeer]

That's what I do as well. I pre heat my mash tun, not to an exact temperature but I just put some boiling water in there that is left once I have recirculated some through my plate chiller at the start of the brew day.
I pre heat my grain to room temp by leaving it in the fermenting fridge the night before brew day.
I then heat the water in the HLT to the same temperatures as Horatio.
It seems to work well and I usually hit my mash temperature spot on.

[far9410]

Hi yeah I get that, just seems more of a faff that's all

[Horatio]

Personally I find it much easier. I pump some water from the HLT into the mash tun and while it's heating the tun I get on with something else. In then drain it and tip the grain in and start to slowly pump the required amount of water into the tun. I don't have to do anything other than occasionally glance at the site glass to check the volume that has gone in. Once it's done it only takes a very quick stir and its all done! Before I underlet I had to stand and slowly pour grain with one hand while stirring with the other, and this was after making sure the strike temp was right! Each to their own though; like they say, if it ain't broke, don't fix it!

[Belter]

Hi yeah I get that, just seems more of a faff that's all

For me the faff is exactly the same but minus the worst step of tipping and stirring. I switched to under letting on the big rig and won't be going back

[chastuck]

Put me straight on this underletting - you put all the dry grain into the mash tun, then you let the mash water trickle in via the outlet tap. Is that right? How do you stop the more flour like bits of the grain from getting through the false bottom holes and clogging the system?

[Belter]

Put me straight on this underletting - you put all the dry grain into the mash tun, then you let the mash water trickle in via the outlet tap. Is that right? How do you stop the more flour like bits of the grain from getting through the false bottom holes and clogging the system?

I don't understand the question. If you don't under let then you'd still have these bits going through your false bottom. They just dissolve

[chastuck]

Put me straight on this underletting - you put all the dry grain into the mash tun, then you let the mash water trickle in via the outlet tap. Is that right? How do you stop the more flour like bits of the grain from getting through the false bottom holes and clogging the system?

I don't understand the question. If you don't under let then you'd still have these bits going through your false bottom. They just dissolve

Thanks for that. I'm keen to try the underletting process as I'm now doing 60L batches and all that stirring-in with a conventional mash standing on a step ladder is killing me! I just want to be clear on the process and I guess I'm concerned that tipping in the dry grain first could somehow get into the outlet pipework and sort of 'set' in the pipe, thus blocking it up.

[Belter]

Put me straight on this underletting - you put all the dry grain into the mash tun, then you let the mash water trickle in via the outlet tap. Is that right? How do you stop the more flour like bits of the grain from getting through the false bottom holes and clogging the system?

I don't understand the question. If you don't under let then you'd still have these bits going through your false bottom. They just dissolve

Thanks for that. I'm keen to try the underletting process as I'm now doing 60L batches and all that stirring-in with a conventional mash standing on a step ladder is killing me! I just want to be clear on the process and I guess I'm concerned that tipping in the dry grain first could somehow get into the outlet pipework and sort of 'set' in the pipe, thus blocking it up.

Never happened to me mate

[Steve D]

First saw underletting on Phil Robins's (Longdog Brewery) homebrew rig. So easy that I started underletting on mine next brew, and never went back.

Pre heat mash tun with boiling water then drain.
Don't run the liquor in too fast
Don't do anything until it's all in and by then you should see liquor appearing at the surface of the grist.
A few stirs and you're done.

Advantages - apart from the obvious not having to manhandle grain into liquor while stirring at the same time...

- Very few if any dry lumps to deal with which minimises stirring. Over stirring can lead to a set mash.
- Liquor entering the mash through the manifold/false bottom clears the area of floury material, bits, cloggy stuff, etc, which in turn also reduces the chances of brewer suicide by set mash.

As a result, hand on heart, I've never even remotely had a set mash since I started underletting.

Disadvantages - can't think of any.

Cheers!

[chastuck]

First saw underletting on Phil Robins's (Longdog Brewery) homebrew rig. So easy that I started underletting on mine next brew, and never went back.

Pre heat mash tun with boiling water then drain.
Don't run the liquor in too fast
Don't do anything until it's all in and by then you should see liquor appearing at the surface of the grist.
A few stirs and you're done.

Advantages - apart from the obvious not having to manhandle grain into liquor while stirring at the same time...

- Very few if any dry lumps to deal with which minimises stirring. Over stirring can lead to a set mash.
- Liquor entering the mash through the manifold/false bottom clears the area of floury material, bits, cloggy stuff, etc, which in turn also reduces the chances of brewer suicide by set mash.

As a result, hand on heart, I've never even remotely had a set mash since I started underletting.

Disadvantages - can't think of any.

Cheers!

Thanks Steve. Great instructions. I take it that after you have drained out the boiling water (and closed the tap!), this is when you tip in the full amount of dry grain?

[Steve D]

Thanks Steve. Great instructions. I take it that after you have drained out the boiling water (and closed the tap!), this is when you tip in the full amount of dry grain?

Yeah, sorry, my omission. I use 2 kettlefuls of boiling water. Boil the kettle pour into mashtun - making sure the tap is shut Clap the lid on, boil another kettle, add that, on with the lid again. Leave it a couple of minutes. Then tip it out quickly and dump in your grain - not forgetting your manifold/false bottom. I felt a right tit when I did that once - and you only do that once! Your liquor will already be at strike heat, right , connect the outlet of your HLT to the outlet of your mashtun, open the taps and you're away. Remember to close BOTH taps when you're done or there will be tears..

Preheating the tun and the fact that there's minimal mixing time means less temperature drop during mashing in, also an advantage. My strike heat is about 9c above initial heat and I don't bother pre-heating the grist (retorrification). I really can't be arsed...

Cheers!

[chastuck]

Thanks Steve. Great instructions. I take it that after you have drained out the boiling water (and closed the tap!), this is when you tip in the full amount of dry grain?

Yeah, sorry, my omission. I use 2 kettlefuls of boiling water. Boil the kettle pour into mashtun - making sure the tap is shut Clap the lid on, boil another kettle, add that, on with the lid again. Leave it a couple of minutes. Then tip it out quickly and dump in your grain - not forgetting your manifold/false bottom. I felt a right tit when I did that once - and you only do that once! Your liquor will already be at strike heat, right , connect the outlet of your HLT to the outlet of your mashtun, open the taps and you're away. Remember to close BOTH taps when you're done or there will be tears..

Preheating the tun and the fact that there's minimal mixing time means less temperature drop during mashing in, also an advantage. My strike heat is about 9c above initial heat and I don't bother pre-heating the grist (retorrification). I really can't be arsed...

Cheers!

Excellent! Thanks for clarification. I'm going to give it a try on my next brew.