Sorry to use the 'E' word again but I've been looking at my efficiency and have been alarmed to see the figure I've come up with is is an improbable 89%, especially when you consider I am batch sparging. The problem either lies in my maths or equipment or my newbie brewer low efficiency expectations. I wondered if someone could take a look at my maths and technique please and see where I am going wrong or right.
Maths
Today I used 4.56kg of pale malt and 40l of water to produce 25l of wort. So using Jim's recipe formulation pages i worked out the following
4.56 * (300/25) = 54.72 potential gravity points
So if I got 25l of 1.049 wort corrected to 20C that means that I extracted 49 of those gravity points so
49/54.72 = 89.5% efficiency - Is this right?
Equipment
If it helps I am using the lauter tun I made for my mini mash which is 2 10 gallon buckets one inside the other they measure 11 inches wide by 10 inches deep and only seem to have room for about 5-5 litres of liquid when they have 4.5kg grain in them. This fact necessitates that I am forever recirculating running and batch sparging in 4 litre batches. Could this be the cause of the high efficiency reading?
I know it's how good the beer tastes that really matters but it's something I'd really like to understand.
Cheers for your patience
JP
