Underletting
Underletting
I have mashed for years using the method of filling the mashtun with treated water at about 76oc and stirring the water until after using strike heat calculators the temperature was suitable to add the grain. This only takes a matter of 2 to 3 mins and the desired mash temp is dead on. But during that 2 to3 mins the temperature of the grain must be to high for a short time. I have a large tube with which I could use for underletting in which case the grain would never be to hot. What would you do?. Have you ever thought that the first grain to hit the water might be affected by the initial heat.
I mash 20 lb of grain from two buckets into 20 +litres of mash water so it does take a little longer than a standard 23 litre brew.
What do you think of underletting?. It sounds so easy just fill the mashtun with grain and open the tap and gently stir, Is it so easy?. I shall mash on Saturday.
Thanks for any replies
I mash 20 lb of grain from two buckets into 20 +litres of mash water so it does take a little longer than a standard 23 litre brew.
What do you think of underletting?. It sounds so easy just fill the mashtun with grain and open the tap and gently stir, Is it so easy?. I shall mash on Saturday.
Thanks for any replies
- Aleman
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Re: Underletting
I under let and it really is that easy. Don't transfer the water too quickly or you will lift the dry grain.
I use a Paint Stirrer on a cordless drill for final mixing . . but that is just because stirring a 50L or 80L mash tun with a stainless spoon is a PITA.
I stand my mash tun next to the hot water tank for a couple of days to bring the grain temp up which helps with strike heat and prevents thermal shock to the enzymes.
I use a Paint Stirrer on a cordless drill for final mixing . . but that is just because stirring a 50L or 80L mash tun with a stainless spoon is a PITA.
I stand my mash tun next to the hot water tank for a couple of days to bring the grain temp up which helps with strike heat and prevents thermal shock to the enzymes.
Re: Underletting
I'm sorry I don't fully understand (having one of those days) Could you explain exactly how this works exactly? And what exactly is the process? I've never been too concerned but I notice wit hthe bigger mash volumes it takes longer and longer to come in on target
Re: Underletting
Basically instead of adding the grain to the water in your mash tun, you put the grain bill into the mash tun and then slowly add the heated water through the false bottom/manifold of the mash tun.
Because the water enters from underneath it is called "underletting" and is one way of handling doughing in with bigger grain bills.
Cheers
Steve
Because the water enters from underneath it is called "underletting" and is one way of handling doughing in with bigger grain bills.
Cheers
Steve
Re: Underletting
Is it quicker to underlet? Can see how it helps mange a big grain bill, but surely the strike temp is the same so you still have a period at the start when it is hot. How do you pre-heat the tun with under letting?
Edit- just read about dry heating grain and tun, so less difference in strike temp
Edit- just read about dry heating grain and tun, so less difference in strike temp

- Andy
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Re: Underletting
I add a few kettles worth of boiling water to the tun, seal it up and leave it for 15 mins or so. Then drain out and it's ready to go.Martin G wrote: How do you pre-heat the tun with under letting?
I underlet when mashing in also

Dan!
Re: Underletting
My main concern is that adding grain by tipping a 20 litre bucket under my left arm and stirring with the other hand leaves a time when the heat on the grain is above the mash temp I aim for usually 670c. This is until all of the grain is in the mashtun when it will be 67oc.
With the cold grain added to the mashtun the incoming water would not go over the perfect mash temp. It sounds ideal to me.
Will mashing this way make a difference to the wort?. What do you think?. I can easily mash in my normal way water in the mashtun and add the grain. I have done it this way for over 30 years, ahh the old Bruheat Bucket. I am just looking to improve things. But will I?. Will it make a difference.
Happy brewing
With the cold grain added to the mashtun the incoming water would not go over the perfect mash temp. It sounds ideal to me.
Will mashing this way make a difference to the wort?. What do you think?. I can easily mash in my normal way water in the mashtun and add the grain. I have done it this way for over 30 years, ahh the old Bruheat Bucket. I am just looking to improve things. But will I?. Will it make a difference.
Happy brewing
- Aleman
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Re: Underletting
A difference to the beer . . . Probably not
It made a difference to my brewing . . . it made it easier, No Dough balls, and easy stirring . . . just as quick as tipping grain into hot water, but only one hand needed rather than three
It made a difference to my brewing . . . it made it easier, No Dough balls, and easy stirring . . . just as quick as tipping grain into hot water, but only one hand needed rather than three
Re: Underletting
Thank you to all that replied, you are what makes the site great.
Thanks again.
Thanks again.
- jmc
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Re: Underletting
I do the same. 2 full kettles of boiling water (2 x 1.5L) in my ~47L coolbox-mashtun to warm it up.Andy wrote:I add a few kettles worth of boiling water to the tun, seal it up and leave it for 15 mins or so. Then drain out and it's ready to go.Martin G wrote: How do you pre-heat the tun with under letting?
I underlet when mashing in also
Drain, add grain then underlet.
Underletting pic from the weekend. Liquor from HLT to MT via tap.

Brew length 42L. Just needed a quick stir.

- far9410
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Re: Underletting
Could you just add the water on top of the grain and stir?
no palate, no patience.
Drinking - of course
Drinking - of course
- Aleman
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Re: Underletting
No, ultimately it just sits on top going nowhere, and you get massive dough ballsfar9410 wrote:Could you just add the water on top of the grain and stir?

- far9410
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Re: Underletting
Ok thought so.Aleman wrote:No, ultimately it just sits on top going nowhere, and you get massive dough ballsfar9410 wrote:Could you just add the water on top of the grain and stir?

no palate, no patience.
Drinking - of course
Drinking - of course
Re: Underletting
obviously youd need to pump hlt water into mashtun or the head pressure from the mashtun filling up wouldn't allow much hlt water if doing it from gravity???
nice idea will give it a go, pita them doughballs bastards
nice idea will give it a go, pita them doughballs bastards