In 2017 Black Donkey initiated a project, the “Wild Yeast Chase” in conjunction with IT Tallaght and Enterprise Ireland, to harvest wild yeast strains from the Roscommon countryside. The goal was to isolate a unique, strain of yeast, indigenous to the locality of the brewery that will become the base for new recipes, which are truly unique to Black Donkey.
Located at Rathcroghan,east Roscommon, is a heritage site extending over 6 square kilometres encompassing national monuments, natural limestone caves, burial mounds and ringforts. The ancient landscape was witness to the rise and fall of great tribes, chieftains and dynastic families. It was home to the great Iron Age Warrior, Queen Medb who ruled all of Connaught from Rathcroghan, and also legendary heroes Battle Goddess Morrigan and the boy hero Cúchulainn.
Work started here last Halloween when we gathered yeast samples from Oweynagat cave, also called ‘Hellsmouth of Ireland’, one of the many natural limestone caves. These samples returned to IT Tallaght where they were isolated, purified and yeast strains identified. The resulting samples were then propagated, monitored, analysed and classified. Three successful strains returned home to Roscommon in early January.
On March 8th 2018 the first viable yeast strain called ‘Morrigan Strain #1’ was used in a pilot batch of Underworld and a full production batch was released as part of the ‘Unhinged’ series in June 2018. Due to unprecedented demand for Underworld we have decided to continue to brew this uniquely Roscommon recipe as the first in our ‘Brewhouse Reserve’ range of beers.