A master at work

One of only a few people in the world who is qualified as both a Master Brewer and Master Distiller, Dr Gearóid Cahill talks to Amy Molloy about his career with Diageo before making the move to the Boyne Valley, where he leads production at Slane Irish Whiskey.

Dr Gearóid Cahill’s successful career in the drinks industry has earned him many impressive titles, but he still considers himself “ just a wonky scientist at heart.” The Westmeath native has worked in brewing and distilling for more than 25 years and is one of the few people in the world who can call themselves both a master distiller and master brewer. Another claim to fame is that he is one of an elite group that knows the secret recipe behind Guinness, a secret he says he will “take to the grave.”

Dr Cahill spent 19 years with Diageo working in a variety of global technical roles, leading process and product improvements while developing and rolling out standards in brewing and distilling plants in Kentucky, Nigeria, Ghana, Kenya, Jamaica, the UK and Ireland. He also led the development of a €47m investment in new production processes at St James’s Gate in Dublin. “The best decision I made in my life was to join Guinness – and the second-best decision was to leave 19 years later,” he says. “It was a really tough decision. I was sitting on that for over a year, but the timing was about right. I felt I had started to become part of the furniture.”

One of only a few people in the world who is qualified as both a Master Brewer and Master Distiller, Dr Gearóid Cahill talks to Amy Molloy about his career with Diageo before making the move to the Boyne Valley, where he leads production at Slane Irish Whiskey.

Good timing with decisions has reaped him many benefits during his career. None more so than the moment he chose to study biotechnology at DCU. A love of all things science and engineering meant the degree was an obvious choice for him. “I’m one of the few of my classmates who still uses a lot of what I learned to this day,” he says. His studies also introduced him to his life partner. A brewing romance with classmate Angela O’Toole in second year eventually fermented into marriage. Four children and two grandchildren later, the couple are still going strong. “Angela is in adult education and is a senior manager looking after the educational training of those who didn’t have lucky breaks, so that’s what fires her up and gets her going,” he says.

At 56 years of age, and despite his many academic qualifications, Cahill is still hungry to learn more. He graduated with a BSc in Biotechnology (1987), MSc in Biotechnology (1990), a PhD (1999) from DCU and most recently he was awarded the prestigious accolade of Master Distiller from the Institute of Brewing and Distilling (IBD) in London.

In 2019 he joined Slane Distillery in Co Meath as distillery manager and is now the company’s first ever Master Distiller. The role involves working closely with colleagues at Brown-Forman in the US to optimise production across all three whiskey types – malt, pot still and grain whiskey. He has also been instrumental in driving improvements in water and energy usage within the distillery, increasing sustainability in the whiskey making process. “For anyone who thinks we sit around in tweed sipping whiskey all day, it’s actually quite an active role with lots going on,” he says. “It’s a great job. We have a small team here. In my current job you are the technical reference point. You are the linchpin, you are the technical guru, you’re the manager, you’re responsible for getting it all running well, but you’re also a brand ambassador. You have to be able to represent the brand.”

Before entering the drinks industry, he was a process operator with Interbio Limited. He then spent five years working as an environmental specialist with Bord na Móna. His sights, however, had always firmly been set on a job with Guinness. When studying biotechnology he had the opportunity to make beer and was fascinated by what living biological microbes could do. After 10 years of trying, and “sometimes being overqualified and underqualified”, he finally landed the job he dreamed of in 1996.

He held various roles including development technologist and head of science. During his time at Guinness, the company offered him the opportunity to study for a PhD as part of his day job and he eventually became a Master Brewer. “I used to do a lot of troubleshooting, trying to get the plant to produce a very consistent product as every year mother nature gives us different crops of barley. I was one of the handful of people in the world that knew the secret essence of Guinness. “In Guinness, it used to be all about research, publications and academia, but it had changed focus in recent years. They were looking for shorter term goals, and for me, particularly in my role, as I was head of technical, science and innovation, I decided it was time for a change.”

That change involved a move to distilling. His skills were transferable as the first half of whiskey making is “effectively the same as beer making.” He joined Alltech’s state-of-the-art research centre in Dunboyne, Co Meath in 2015, leading a program focused on optimising distillery brewhouse operations for grain whiskey production using enzyme technology and novel process innovation. The opportunity to work with Slane Irish Whiskey, a relatively new brand, arose in 2019 and it’s a role he is thoroughly enjoying. While there are similarities between brewing and distilling, the two are also like “completely different worlds,” he says. “I only finished my Master Distillers’ course last summer. For me it was great – now I’m thinking how will I apply this knowledge and maximise the benefit for Slane. On a daily basis, I continue to use the academic skills I have acquired to address problems and drive process improvements. It is very satisfying and makes it all worthwhile.”

Amy Molloy is Public Affairs Correspondent with the Irish Independent