Water to Grain Ratio

[JammyBStard]

Can anyone tell me what difference mashing at different water to grain ratios makes to the mash aside, from the obvious difference in sugar levels.
Is there a min/max ratio?

I'm trying to work out the limits of my 24L mash tun.

[escapizm]

Often 2.5 :1 grain to water

[Scooby]

I use a 24l tun and if continuous sparging og's of 1.070+ are achievable. Batch sparging with 2 equal sparges will reduce that to sub 1.050 modifying the batch sparge will allow higher gravities ie drain the mash and then do 2 equal sparges or do 3 equal sparges

[alefric]

Often 2.5 :1 grain to water

Yep i do the same thing but often start at 2.3 :1 in case i need to adjust the temp with either hot or cold water.

[mctoon]

I use a 24l tun and if continuous sparging og's of 1.070+ are achievable. Batch sparging with 2 equal sparges will reduce that to sub 1.050 modifying the batch sparge will allow higher gravities ie drain the mash and then do 2 equal sparges or do 3 equal sparges

Scooby, so you are saying drain the mash first,, then do 2 or 3 batch sparges,,,

as oppose to "top up the mash",, with say 6ltrs for the first bath,, then top up with say 16Ltrs for the second batch

[Scooby]

Yeah, for example if I did a brew with 6kg of grain I can work out for my system that would require 38.5l total. The mash would be 15l and the top up in a normal 2 batch sparge would be 7.6l and a 2nd of 15.9l

15l + 7.6l + 6kg grain won't fit in the tun, so drain the tun and split the remaining 23.5l in two and sparge with 11.75l which together with the grain will fit.

Or you could calculate for three equal sparges without draining the mash, (top up drain, then 2 more all with equal run off) I haven't done that as mostly I brew low to medium strength brews and the method above has suited me so far.

[mctoon]

Cheers Scooby,, will try that idea,, my last couple of brews aint hit the OG so will give it a whirl

[Scooby]

Do you know what you efficiency is?

Did some quick working out with 3 equal batches. The amount of top up required for the first sparge gradually decreases as the grain increases. (Logical as you are collecting the same amount of preboil wort irrespective of the strength) There comes a point where the run off from the mash without topping up and the run off from the 2nd and 3rd additions is the same, I reckon that is approx 6.5kg. If you mash with more grain there isn't enough water left to top up and do the 2nd and 3rd sparges with an equal run off so efficiency would suffer. You could use more water than is required and prolong the boil to reduce but it's not a good idea.

All the above was worked out 2.5:1 but when batch sparging the ratio makes no difference to amount of grain you can mash as you still have to put the same amount of water through the tun (The mash vol will be less but the top up more)

For my system that would mean a beer with and OG of 1.057