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Castle Rock's "DIPA: Simcoe, Mosaic" drops Saturday 7th August


Following the success of SIPA: Simcoe and SIPA: Mosaic, we thought it made sense to combine them with a double IPA hopped with Simcoe and Mosaic.

Strictly and scientifically speaking, that’s not at all what happened but let’s go with it for the purpose of this intro. Double the hops and double the ABV. And the result, doubly as good?

We’ll let you be the judge of that.

Read on for the more technical process behind the pint, straight from the horse’s mouth: our developmental brewer, Matt.



ABV – 8.5%

IBU – 45

Dry Hop Intensity – 15g/L

MALT – Extra Pale Ale Malt, Torrefied Wheat, Oats

HOPS – Simcoe, Mosaic leaf (kettle); Simcoe, Mosaic T90 pellets (dry hop)

YEAST- London Ale iii

Sulfate:Chloride Ratio – 1:2



Our latest release, brewed with our incredibly talented friends at Attic Brew Co. is a Double IPA. A big and hazy, fresh and juicy hop-bomb brewed for the epicentre of the British summer.

This beer is crammed full of hops; balanced by a ton of residual sugars from the malt bill; softened by a chloride-heavy water profile and hazed up by wheat, oats and a London Ale iii yeast strain.

No matter what the weather is doing, we hope to honour the DIPA style and offer liquid sunshine for your beer glass. It has been lovingly brewed and packaged by the team at Attic, every can wrapped in our Liv’s incredible pattern heavy artwork.

Enjoy with friends at home, down the pub or – we can finally say it – at a beer festival (we’ll be showcasing this one at alongside some other bangers at Nottingham Craft Beer Festival).

We wanted to brew you an 8.5% showstopper and give ourselves the excuse to combine and explore two of our favourite hops: SIMCOE and MOSAIC.  Please enjoy mindfully.


We added a generous dose of Simcoe and Mosaic leaf at the end of boil to achieve our target IBU and extract a heap of aromatic oils from the hop. This helps set up a really solid base for the hop profile which then gets sent into hyper-colour by a post fermentation dry hop addition of Simcoe and Mosaic T90 pellets. We dry hopped at 12°C to achieve a more fruit heavy aroma from the hops, rather than the dank, resinous aromas achieved at higher dry hop temperatures.

Both Simcoe and Mosaic have complex aroma profiles and can lend multiple qualities to a beer depending how you treat them. Simcoe is known for passionfruit, citrus, and pine notes, while Mosaic can lend tropical fruit, stone fruit and berry notes. Interestingly (if you are into hop genealogy, not everyone is…), Mosaic is the ‘child’ of Simcoe, having been bred originally from Simcoe and a Nugget derived male plant. So, you could look at this as a family reunion, or the school run, or something.


We have kept the malt bill fairly simple for this one as we wanted to let the hops do the talking flavour-wise. An extra pale ale malt is used as the base , giving us the bulk of the extract for fermentation, combined with torrefied wheat for head retention and a generous heap of oats, to increase perceived body and sweetness.


We used London Ale iii yeast to ferment this beer; its ester profile of stone fruit balances well with a heavily dry hopped beer. It also lends a satisfying “chewy” mouthfeel to the beer, as it has low attenuation properties, or to put it another way, it leaves a lot of sugars unfermented once fermentation has ended. It also has low flocculation properties, which means a lot of the yeast cells remain in suspension after fermentation and combine with hop matter and proteins to give the beer its hazy appearance, typical for this style.


The brewing liquor was treated with a 1:2 sulfate:chloride ratio, which softens the perception of bitterness and helps to create a fuller mouthfeel. We are really happy with the water profile we have been using for our recent pales, and this year’s can and keg beers have been brewed consistently with it.


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