mash versus sparge volume when using less grain

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I get typically get quite a high mash efficiency, so when I scale a recipe using BeerSmith 3 I get a relatively small amount of grain.

Recently I've noticed however that I've been ending up with a small volume of high gravity first-wort ... and doing quite a lot of sparge which gets very watery towards the end.

As I seem to remember reading somewhere that one should aim to get around half of the overall wort from the mash, I thought I'd look a bit closer at what's going on. [EDIT: apparently Palmer says it's common to use 1.5 times more water for sparging as was used for mashing, but this seems like a bit of a sweeping generalisation].

So if we call the proportion of the overall wort from the mash the 'mash volume ratio' then:

Screenshot 2022-04-13 at 18.04.37.png


... or in terms of the mash and equipment parameters:

Screenshot 2022-04-13 at 18.05.10.png


Lightbulb moment... 💡 If you reduce the grain weight without changing anything else, then you end up getting less of your overall wort from the mash and more from the sparge.

So what can you do about it?

Well with BS3, the easy answer is to bump up the water-to-grain ratio in the first mash step - et voila!
 
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Wowser. I never sparge more than 2 litres! Plus abut 4 litres of lautering.
 
I use a 3v system and mash with around 13l and sparge about 23l,losses gives my the 23l to fv.
I notice all in one users are approx reverse this as there's the recirc volume requirement in the mash.
On my brew last week on the robobrew I had 22l of strike and 12l of sparge with 23l to the fermenter with losses being 6l to grain and 5 to boil off and around 72% efficiency according to Brewers Friend though post boil was 1.060...
 
On my brew last week on the robobrew I had 22l of strike and 12l of sparge with 23l to the fermenter with losses being 6l to grain and 5 to boil off and around 72% efficiency according to Brewers Friend though post boil was 1.060...
5l sounds like quite a bit of boil-off; maybe that includes trub losses? Anyhow that would make your pre-boil volume about 28l of which 16l (57%) came from the mash - does that sound about right?

And with 22l of strike to 6kg grain, you‘d have a mash thickness of 3.7 litres per kilo - which sounds consistent with the high proportion of your overall liquid coming from the mash versus the sparge athumb..
 
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Apologies but I'm not ashamed to admit I'm not quite sure what you mean by 2 litres of sparging plus 4 litres of lautering... could you spell it out for me? thanks

I take the grain bag out of the boiler and put it in a salad drainer (is that the word? Those big sieve things with an extendable frame) which sits on top of the boiler and allows it to drain. This whilst I have turned the boiler full on and it is moving towards boiling point. Then I draw off 2 litres of the wort from the boiler tap, and slowly pour it over the bag in the sieve, and allow it drain. Then repeat that, so that's the 4 litres of lautering. Then I pour 2 litres of hot water slowly over the bag, and allow it drain. Finally I take the bag out of the sieve, and place it in a small bowl with some spacers in the bottom. Press down hard on the bag with my knuckles (I'm wearing clean Marigolds, of course!), replace it in the sieve, and pour the liquid back in the boiler. I repeat this process four or five times. By then, the wort is nearly ready for the hops.

But I suspect little of this will be relevant to you guys' methods.
 
Well with BS3, the easy answer is to bump up the water-to-grain ratio in the first mash step - et voila!
I've done this for as long as I can remember, as I weigh everything out and treat all my water the night before. I use the same water for both mash and sparge. In BS, I adjust the water grist ratio to a get a nice round number for my mash water volume. Typically for a 12L batch I may require, say, 22.6L over all, so I aim for 10L to heat to strike temp and mash in. For me, it simplifies getting up and running on a brew day. The remainder I sparge with.
 
I don’t sparge/lauter as such but do 3 mashes. With 4-5 kg of grain the first mash uses 3 gallons (15 litres) of strike water and yields around 1.5 gallons of high gravity wort. Second and third (half hour) mashes use 2.5 gallons of water and yield 5 gallons of medium and low gravity wort. A squeeze of the grain bag can yield another 0.5 gallons making a total of around 7 gallons of wort that after a one hour boil yields 5.5ish gallons for the fermenter.
 
I draw off 2 litres of the wort from the boiler tap, and slowly pour it over the bag in the sieve, and allow it drain. Then repeat that, so that's the 4 litres of lautering. Then I pour 2 litres of hot water slowly over the bag, and allow it drain.
Ah! OK - got it: so the lautering is similar to me recirculating hot wort through the mash tun.
Thanks for clearing that up, it‘s really interesting to understand different peoples processes :-)
 
I've done this for as long as I can remember, as I weigh everything out and treat all my water the night before. I use the same water for both mash and sparge. In BS, I adjust the water grist ratio to a get a nice round number for my mash water volume. Typically for a 12L batch I may require, say, 22.6L over all, so I aim for 10L to heat to strike temp and mash in. For me, it simplifies getting up and running on a brew day. The remainder I sparge with.
Yes I totally agree it helps a lot to do your water the night before. Gets you going quicker and one less thing to worry about on the day :-)
 
You're bang on as I did forget to mention trub losses
5l sounds like quite a bit of boil-off; maybe that includes trub losses? Anyhow that would make your pre-boil volume about 28l of which 16l (57%) came from the mash - does that sound about right?

And with 22l of strike to 6kg grain, you‘d have a mash thickness of 3.7 litres per kilo - which sounds consistent with the high proportion of your overall liquid coming from the mash versus the sparge athumb..
You're bang on as I did forget to mention the trub losses and to add the reason for viscose mash was due to the rye and wheat malt addictions which can be a right pain as I don't use rice hulls.
 
Ah! OK - got it: so the lautering is similar to me recirculating hot wort through the mash tun.
Thanks for clearing that up, it‘s really interesting to understand different peoples processes :-)

Yes, exactly that. I think I picked up on an idea from another poster here, It's no trouble to do whilst I'm waiting for the wort to reach boiling point, and has improved my efficiency a bit. I might add that as far as large grain bills are concerned, I limit the size of my batches for Health and Safety reasons as much as anything else, manhandling heavy bags of wet grain can be a dodgy business. So I don't go bigger than 4 kg max.
 
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