Trying to understand this recipe!.

[malky1841]

Hi folks. Just starting on my journey into wholegrain brewing after years of kits.
I bought this book that I hear a lot of folk lamenting about, Homebrew Beer by Greg hughes.

On page 150 for the recipe for a winter warmer it asks for.

Liquor for the mash 13.75 litres. Total liquor for recipe 32,5 litres.

The page on how to read the recipes states for the mash "The water required for mixing with the grains in the mash tun. Use the total liquor for sparging".

So I add 13.75 liters to my mash tun add the grains and mash for an hour then sparge into my boiler with 32.5 litres?. that gives me 45.80 litres in total before the boil !.

Next it says in the recipe for the boil "27 liters" which in the recipe instructions states "The estimated volume of water required for the boiler once the mash has been sparged".

Now having not not done this before I calculate that Ill have added 45.80 litres of water after the sparg!. Surely the grain won't soak up 18 odd litres of water before the boil?.

Am I being stupid?. Should I just sparge with the sparge volume until I hit 27 liters in my boiler?.

 

[kh54s10]

I do batch sparging. I use the calculation for the mash. 1.25 to 1.5 quarts per pound of grain. (you'll have to do the conversion) I have a dip stick that tells me how much is in my boil kettle. I measure how much I collected from the mash, then sparge with enough to get the rest. You need to know your boil off. I usually boil off 2 gallons per hour. So to get just over 5 gallons into the fermenter I need to have just over 7 gallons, preboil.

Grains absorption is pretty constant, I don't know what the calculation is but you should be able to do a search for it.

 

[dmtaylor]

I understand your confusion. I'm sure the intent is for 32.5 litres total water to be used. This includes the initial 13.75 litres. So, for the sparge, you actually need to use 32.5 minus 13.75 = 18.75 litres for the sparge.

Next, given that the grains will absorb and permanently retain approximately 6-7 litres of water or so that you will never be able to extract, the overall total of 32.5 litres is reduced by that amount to the 27 litres that he specifies for the pre-boil (personally I think it will actually be closer to 26 litres).

It's all good. Just a bit confusing. Hope I've helped.

By the way, I find grain absorption to be 0.12 US Gal per US lb. In metric this converts to almost exactly 1 litre/kg.

 

[malky1841]

Ahh that makes more sense!. Why would it say to use the total amount of Liquor for the sparge?. Is that a misprint ?.

 

[dmtaylor]

No, he's just trying to mess you up.