question re recipes for AG

[PD]

I've just got hold of Graham Wheelers book and had the briefest of scans through it so my question might already be answered when I come to read it.
I will be using a 28litre boiler and a 30-40 litre mash tun, I intend brewing 19 litre batches
In the recipes it says total liquor ( 26.6 litres )
Mash liquor 8 litres
can someone explain how I use these figures when doing the brew...
Is Mash liquor (8 litres ) the amount to go into mash tun along with grains, do I then mash and sparge to get as near to the total liquor of 26.6 litres as I can, which is then added to my boiler to begin the boil. Boiling it down for the recommended time and hopefully arriving at my 19 litre brew length
Is that the general gist of it ?

Above not taking into account dead spaces in mash tun / boiler etc which I'm currently determining.

Sorry for being a brain dead.

 

[Good Ed]

That's basically correct. The mash liquor is based on 2.5L per kg of malt, and this the volume that goes in the mash tun with your grain.

GW does state (page 85) that the total liquor figure is an indication of the total amount of liquor that you need to treat prior to brewing. You might want to work this out yourself, and for sparging I just fill my HLT up to the brim and use what I need to get to the pre boil volume. This is what you need to work out over time as you get used to your system.

Very simply pre boil volume (what you need to get after sparging) = brew length + dead space of HLT + loss due to hops displacement and absorption, 1.6L/100g of hops + loss due to evaporation, I use a figure of 9% per hour + 1L for loss of volume in cooling from 100C to 20C.

 

[PD]

yes got that thank you. I thought I was correct in my head. Is your efficiency measured on the amount you get out after sparging and into the boiler.... so 100% would be when you got the exact brew amount

 

[Good Ed]

No, efficiency is really working out what SG you get from the malt; I used to worry about that and work it out, but apart from arriving at a figure to plug into your brewing software it's not worth worrying about. When brewing on a small scale it doesn't really matter if you use 4.75kg or 5kg of malt to get to you pre boil gravity. Most recipes are based on 75% efficiency, working with my system it's about 73%, although the brew I'm doing tomorrow is 67%. All new brewers worry about efficiency, but you will soon work out your brews to your system, and your goal should be to produce what you like, and bugger the efficiency.

 

[PD]

well said.