Brewer’s Notes – SIPA: Mosaic

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Earlier this year, following a couple of cans we were really pleased with (NEIPA and West Coast SIPA), we brewed SIPA: Mosaic and it quickly became an in-house favourite. Our mutually beneficial brewing partnership with Attic Brew Co. was still in its early days then but one year on and two collab beers later, it’s still going strong.

So, to celebrate, SIPA: Mosaic is back – and this time in keg, too. A Christmas treat to everyone else that loved it so much, and to those that didn’t get to try it the first time around.

(Also here for the festive season is Chocolate Orange Stout, which you can read about here.)

Read on for notes straight from the horse’s mouth, our developmental brewer, Matt.



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 used extra pale malt for the base of the grist in this beer, this gives the beer a light colour and provides a subtle, low key flavour profile.

A higher mash bed temperature of 68⁰C leaves plenty of residual sugars in the finished beer after fermentation, as it produces more unfermentable sugar. When combined with the addition of oats, this lends the beer a smooth and full mouthfeel.


Attic’s London Ale III yeast strain was used to ferment this beer, giving lots of fruity esters. It has low attenuation characteristics, which means the yeast leaves a lot of sugars unfermented relative to other yeast strains. This gives the beer a really ‘chewy’, full and lingering mouthfeel. It packs a whole lot of flavour for a low ABV, session pale.


We chose to showcase one of our favourite hops, Mosaic, as the one and only hop in this beer.

It’s a hop with a lot of depth, displaying tropical fruit, passion fruit and blueberry characteristics, as well as more aggressive pine and grapefruit notes. It brings a LOT to the table.

For SIPA: Mosaic, we’ve dry hopped at 16g per litre, with the aim of providing a really tasty amount of aroma.

The beer has an IBU level of 30, a suitably low level of bitterness, to let all the flavour from the Mosaic come through and do its thing.

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