AG#28 – Imperial Stout (Exceeding the Mechanical Limit!)

Posted by: pdtnc on: June 5, 2010

In: Brewing
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AG#28 – Imperial Stout (Exceeding the Mechanical Limit!)
Things were going really well until I took a pre-boil gravity and realised I was way off the mark!
Possibly needed a longer Mash duration and probably needed a higher percentage of Pale Malt to fully convert the other malts & adjuncts. I had assumed that the combined percentages of Pale Malt, Wheat Malt & Munich Malt would have been enough for the Mash to convert OK
I kind of rescued the OG partially with a couple of bags of Dry Spray Malt. Recipe alterations needed!!!

The Mash Tun was exceedingly full and I was wondering how I would sparge but it actually sparged really well with 3x 5Litre top-ups following an initial run-off of 5Litres. I started really early and was all done with ‘something’ in the FV, yeast pitched, around 11.30am 🙂
Fermentables:
Pale Malt – 2450g – 32%
Wheat Malt – 1530g – 20%
Munich Malt – 1150g – 15%
Caramalt – 765g – 10%
Roasted Barley – 305g – 4%
Chocolate Malt – 305g – 4%
Flaked Barley – 305g – 4%
Flaked Maize – 230g – 3%
Flaked Oats – 150g – 2%
Black Malt – 150g – 2%
Brown Malt – 150g – 2%
Amber Malt – 150g – 2%

Hops:
Admiral @ 60 mins 70g
Whitbread Golding @ 10 mins 20g
Bobek @ 0 mins 10g

Final Volume: 15 Litres
Original Gravity: 1.110
Final Gravity: 1.034
Alcohol Content: 10.1% ABV
Total Liquor: 27.2 Litres
Mash Liquor: 19.2 Litres
Mash Efficiency: 75 %
Bitterness: 80 EBU
Colour: 464 EBC

The Pictures of this cock-up:
Mash Temp:

First Runnings:

FWH:

Boil-over after adding DSM:

OG:

At least 4 times as much Nottingham Yeast as I’d put in a normal brew:

I will brew something like this again, with a better recipe!!! Though I’ll probably need some more Roasted Barley before I do.

This mornings (the day after) Yeasty Action:

This is currently threatening the bucket lid!

*Bottled 16th Jun ’10 with 25g Muscovardo sugar

*Taster Bottle 7th Aug 2010
Fair enough, I’ve Just cracked open a tester 😉
Pours thick and Black with some ruby/brown tints to the head, though the head soon dies down leaving just a subtle carbonation.
The Aroma is alcohol!
The Body is amazing, thick, smooth and creamy.
The taste has mellowed pretty well, the liquorice notes are still there but more subtle.
Bitter edge is like the bitterness you get from really dark chocolate with some powderiness as if like Instant coffee.

I best leave well alone now for 6 months or so 😉

*16th May ’11 Taster:
Big on the liquorice still, smooth and very drinkable, it really is worth making these big mad beers just so you can appreciate how time changes them for the better.