On Imperial Stouts (or The Gratuitous Krausen Appreciation Society)

In November 2017 I planned an Imperial Stout with a short brew length to see what the biggest beer was I could get out of the kit and mash tun (at that time).

I’ve had some great Imperial Stouts over that year and Winter seemed just the right time of year to be thinking of brewing big roasty, toasty, viscous, vineous Stouts of that ilk.

This was a bit bigger than anticipated…

It needed Fruit….

It needed Time…

And now its on oak!

I had half an eye on a few competitions in 2018 and the Homebrew Expo as part of the Manchester Beer Week.

So I set down to plan the recipe.

I like a roasty and toasty Impy, but I wanted something that had hidden strength to it: a softness that belied it’s strength, so opted for an oatmeal stout as the base recipe.

The Recipe

As ever, the Brewing Classic Styles book was a good yardstick for my recipe formulation.

• 3.40 kg – Pale Malt, Maris Otter

• 0.12 kg – Black (Patent) Malt

• 0.12 kg – Chocolate Malt

• 0.12 kg – Roasted Barley

• 0.14 kg – Oats, Flaked

• 1.00 kg – Munich Malt

• 0.10 kg – Wheat, Torrified

• 0.12 kg – Caramel/Crystal Malt -120L

• 0.12 kg – Caramel/Crystal Malt – 60L

  • 0.50 kg – Light Dry Extract – (7.7%) – 15.8 EBC
  • 0.25 kg – Brown Sugar, Dark
  • 60.0 g – Northdown – Boil 60 min (52.0 IBUs)
  • 20.0 g – Fuggles – Boil 30 min (11.0 IBUs)
  • 20.0 g – East Kent Goldings (EKG) – Boil 30 min (9.5 IBUs)
  • Steep Aroma Hops 20.0 g – Flyer – Steep 20 min (8.2 IBUs)

1 pkg – Dry English Ale (White Labs WLP007)

The Process

Nothing particularly unusual: a big grain bill with some dried malt extract and various simple sugars sugars to provide more easily digestible food for the yeast to get a lower final gravity but keeping some complexity from the darker sugars.


Here are the first runnings. It was like engine oil!

After vorlauf and sparging I collected enough for a post boil volume of about 10 litres. The sugars and dried extract in the grist were dissolved in the boil kettle and the OG was 1.111


I pitched the yeast (a one litre starter was necessary) and after a surprisingly short lag time, I checked on progress:


it was clearly happily fermenting away and had no problems with the high OG. Turns out WLP007 is very happy with a big beer!

This is also one of the more surreal ‘yeast sculptures’ I’ve seen over the years.

Aging on fruit

It was a great beer, but lacked punch for the hops or roast in the grain bill. I decided to age it on fruit after my attempts at a date flavoured stout previously.

I took the beer out of the first fermenter and transferred it to a smaller bucket with 200g each of dates, fresh cherries, raisins and sultanas.

It then steeped for a good six months and was mini kegged for the Homebrew Expo in Manchester Beer Week at Beer Nouveau.

It was now over 11% ABV!


It was a bit special. Dark, slight roast but masses of dark fruit.

It was reminiscent of Pedro Ximinez Sherry so it was named PX Approximation for the Expo.

It had some good reviews (we put the beers on unTapped for “honest” feedback.)

And it still carries on… on oak!

After the Expo, there was 5 litres left. I also had 5 litres of an English Porter left over from kegging and blended the two together. This time I put medium toasted American oak chips in it.

It’s kegged now and carbonating, but wow, the oak combined with the richness and fruit really works.

Now if only I could properly barrel age it?!


Use fruit in ageing big beers. The alcohol keeps the nasties away and it really delivers.

Blend finished beers more.

Chuck oak at things.

But keep them within similar styles, colours, hopping etc.

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