Mash volume question

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crd0902

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Hi all I am about to attempt my first all grain this weekend and have a few questions I can't find answers to. I have a recipe kit from a brew shop, it has a grain bill of 4.31 kg. The recipe states a boil volume of 28 litres. I intend to batch sparge in my esky. If I do equal volume sparge that's 14 litres strike water plus 4.31 litres for absorption. So 18.31 litres total. Then maybe 1 litre for mashout. Then 13 litres sparge giving me a total of 28 litres boil volume. Is this correct. Next question if I was to stick to a 3-1 grain to water ratio that makes 17.24 litres strike water leaving 10.76 sparge water. Obviously not taking into account any dead space in my tun or kettle as I don't know this yet. Which way should I be going or are both acceptable. Also if I do work for it what volume of dead space I have prior, when would I add this extra volume. Thanks for you help

Chris
 
Mash at 2.5-3L/Kg

All those figures you quoted will just give you a head ache, so forget them for the time being

Just keep batch sparging until you get your kettle pre boil volume

Once you get to kettle volume and you still have some sparge wort left over you can use that for yeast starter
 
Sorry in the second calculations say 15.07 of sparge water not 10.76
 
G'day crd (Cathode Ray Dude)

Was this meant to be boil-in-a-bag grain kit? I'm guessing it is. While I don't personally agree with it, many (possibly most) BIABs do a full volume boil with no sparge. I also wouldn't be surprised if the store assumed you'd be leaving no or very very little break and trub etc left in the boil kettle or urn. It really won't hurt to give your supplier a ring and ask what assumptions they have made and get fuller recommendations and advice.

Edit added: With a grain bill of 4 point something kilos, I'm making a wild guess that for a normal strength brew, they are intending something like 19 or 20 litres in the fermenter.

Another annoying bloody edit added: With that volume of sparge, it's not a BIAB.
 
Ok cool so would I also sparge that ratio even if it means sparge twice is that what you mean
 
Antiphile no biab full all grain mash and boil and I'm pretty sure it was 22 litres in fermenter. Those details are at home at the moment
 
Geez I hate it when some bloody motorbike hoodlum might be right. But he actually gives good advice this time (thank heavens it'll never happen again this century).
 
Ducatiboy I just saw the rest of your comment regarding leftover wort cheers
 
OK, it just seems the grain bill is a little light on to me for a knockout of 22 litres. I thought I had a pretty good efficiency but maybe they've taken your system into account and expect your mash will be really good.

Can I suggest once the mash is finished, you collect all the wort and pour it through the grain bed again to maximise your efficiency and wort clarity. Then, as the DucatiMan suggests, batch sparge until you get what you're after for your preboil volume.. A good rule of thumb, is to think you'll lose close to 1 litre per kilo of grain to absorption on a first try.
 
antiphile said:
Geez I hate it when some bloody motorbike hoodlum might be right. But he actually gives good advice this time (thank heavens it'll never happen again this century).
When I first started doing AG all those years back I tried to work volumes etc. **** that

In the end it was just easier to keep sparging until the kettle volume was reached after I first drained the tun

Just keep the mash under 3L/Kg and dont worry about head/dead/deep space.

I also add a bout 2lts of boiling water to the mash when its ready to drain first time, as it rinses out more sugars and makes lautering a bit easier
 
antiphile said:
OK, it just seems the grain bill is a little light on to me for a knockout of 22 litres. I thought I had a pretty good efficiency but maybe they've taken your system into account and expect your mash will be really good.

Can I suggest once the mash is finished, you collect all the wort and pour it through the grain bed again to maximise your efficiency and wort clarity. Then, as the DucatiMan suggests, batch sparge until you get what you're after for your preboil volume.. A good rule of thumb, is to think you'll lose close to 1 litre per kilo of grain to absorption on a first try.
And do this for your sparging as well. its called vorloft ( or something like that ) and helps rinse out the suagrs and also clears up the wort nicely and gives less trub in the kettle
 
My apologies I've stuffed up me whole post. Reading the wrong recipe as I bought three kits. It's a 23 L boil and 19L ferment. But still get my answer on the grain ratio. When you say to recycle the wort are you meaning drain the mash, pour back into mash tun, stir, recirculate then drain it again then sparge
 
And how would I do that with the sparge as well. Would I have to drain that into another pot before I drain into my keggle as that would have the first mash drained into it cheers
 
If batch sparging though it's not as straightforward as sparging until you reach your pre-boil. Considering this is brew #1 for you crd and you're doing the maths by hand instead of brewing software, you're doing very well.
I'd suggest brewing software for future brews but for now let's do the maths.

Go 3l/kg of grain as Stu suggests. If you are draining from the esky there will be some residual liquor depending on your false bottom. Work out how much this is as this will be your mash tun loss. Hopefully it's negligable, but let's assume it's 2 litres. Add this to the strike volume.
  • MLT loss = 2 litres
  • Strike volume = (4.31 x 3) + 2 = 12.93 + 2 = 14.93 litres
Allow 1l/kg for grain absorption as this is liquor that won't be transferred to your kettle. It will be thrown out with the grains.
  • Losses to grain = 4.31 litres
If you are doing a 60 minute boil for a 23l batch, you will lose around 5 litres to evaporation but it all depends on your system.
  • Boil loss = 5 litres
To work out your batch sparge volume you work out the difference.
  • Post boil volume = strike water + sparge - MLT loss - boil loss - grain loss
  • Therefore sparge volume is -
    = post boil - strike water + MLT loss + boil loss + grain loss
  • = 23 - 12.93 + 2+ 5 + 4.31
  • = 21.38 litres

So you could do two batch sparges of 10.7 litres each and you should end up with 28 litres into the kettle. If you batch sparged with too much water then once you reach 28 litres (your preboil volume) you will still have some sugary goodness left in your esky which means the starting gravity of your brew will be less than it could be.

Make sure you work out what your final volume is in the kettle and in the fermenter and record both. Also record your OG. Once you have all this you can input this into brewing software and work out your total system efficiency, so that next time you can brew the beer to the strength you want rather than just using a kit.
Good luck!
 
What size is your boiler? I've got a keggle that can squeeze in up to 55lt pre boil. Allowing for larger pre boil gets really good efficiency. 4kg for 23lt I have got beers to 5.3% with that weight. They were dry beers. :chug:
How to get away with a full pot boil is to boil each run off at a time. Add each sparge and re-bring to boil. This gets over the hot break/foaming in segments rather than one big hot break and most likely boil overs.
I mash in esky and aim to batch sparge until the run off gets down to 1.010. Sometimes up to 4 sparges. Sometimes I still don't get down to 1.010 with heavy beers.
Vaurlof well each run off to get the clearest wort. My prosses is probably a lot more fiddly and takes longer but that the way I like to do it.
 
OK RayTube

This is the way I do it (but I'm not saying it's the correct way for anyone else). When I've finished the mash-out (and it seems there's no mash step intructions in that link BTW), I slowly start to drain the wort into a 2 litre container (pyrex jug or similar). After 1 litre is drained, I carefully pour it back into the mash tun trying not to disturb anything as much as possible (and certainly never stirring it at this stage). Then I'll pour another litre and do the same thing. Often at this stage, the grain bed has settled enough to give a liquid from the tap that has no grain or husks in it.

When that's achieved, place a vessel (a fermeneter is good) under the tap or use a silicone hose, and drain virtually all the wort out. Then (again without stirring the grain and pouring it gently over the top as to minimise the disturbance to the grain bed), allow the wort to be filtered again by the grains in the mash tun. Certainly the temp will have dropped by that stage by a reasonable amount but what the heck. Collect that same wort from the tap into a fermenter (or whatever).

Then add your first batch of sparge water so it only covers the top of the grain by a cm or two (again doing it as gently as you can). I like using sparge water a bit hotter than normal because the grain bed has cooled down by probably 5 degrees or more. Then if you want, recycle the first sparge water too.

Keep adding sparge water until you get your desired preboil volume.

I'm not saying this way will work for you, but it's the way I approach it.
 
Ok thanks for your advice. I have a copper manifold for my esky which I will check the loss I get tonight, I have a 50 litre converted keg which doesn't have a dip tube so will be a few litres left after draining as I don't know what will happen with the whirlpool and trub cone etc but will modify this once I workout how it settles. I'll try keep it simple for my first few brews and recirculating and sparging until I get my boil volume makes sense to me so I'll run with that and see how I go. I'll most likely be back with more questions but all good see how we go.

Cheers Chris
 
Pro tip for recirculating sparg : Get an a piece of al-foil ( or a saucer ) and place that on top of your grain bed, then pour your runnings onto that, it will gently flow over the sides and wont cause as much channeling

Basically what you need to do is forget ( most ) the maths and stuff and see what volumes you get. ( Wigmans maths do make sense by the way, and will be useful latter )

You will find things like dead/head/deep space will all vary, as will you evaporation rate ( although it will be constant )

Mash at 2.5-3L/kg

The MOST important thing to do is take note ( as in write it down ) of how much you get from your first running's v how much you initially put in, Further sparging wont use any extra water than your initial running's. Then take note of the evaporation amount. That about all you really need

You need to remember that each brewers setups are different so you cant really give hard & fast answers as they will vary

Its basically a case of suck it and see what you get at the end. Dont get to caught up in the precise maths until you get a few under your belt.
 
Quick update, I checked the loss in my mash tun, 350 ml approx. may be different once I'm mashing grain not just water but we see. I leave approx 4 litres in my kettle as the tap is quite high and have no dip tube. I may need to fix this before brew day as I think that's too much. Cheers
 

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