By: Joshua Kyle
Walled City Brewery is an independent brewery in Londonderry which prides itself in providing patrons with a ’taste of the North West‘ by crafting local, authentic, premium quality, flavoursome beer and food. Inspired by Guinness’ suggested serving of oysters with stout, the challenge was laid down to the brewers to develop a beer using local Lough Foyle oysters and so Foyster Stout was born.
As with all great challenges, research was needed before jumping into the beer-making by looking to other breweries such as Maine’s ’Out-To-Sea‘ imperial stout in the USA or Dublin’s own Porterhouse’s beer, ’Oyster Stout‘.
A sustainably sourced supply of oysters was required for the beer and that’s why we selected the Lough Foyle Irish Flat oyster—the Loughs Agency, operated jointly by Ireland and Northern Ireland, has worked extensively on this species, as have members of the GAIN team. The oysters were sourced from licensed farmers—it is vital for us and for our customers that we use the best ingredients from sustainable suppliers.
The use of the oyster had a dual purpose in the brewing process. Firstly, the flesh was used in the mashing process which extracts natural sugars—the flesh gives a fantastic marine essence to these sugars. Secondly, the shells contain a high amount of calcium carbonate which is used as clarifying agent of the beer. This ensures every part of the oyster is used and nothing is wasted.
The Walled City Brewery launched the beer on 12th October, 2019 which was widely well received. It will be going on sale as a seasonal beer and Foyster Stout will be available in selected bars and restaurants in the city. We’re grateful to the Loughs Agency for their support in our development of this new beer which will help raise awareness for the Flat Oyster.