It’s almost like having three sons. I love them all, but I have to focus on each one at different times to make them the very best they can be.

– Master Blender Dr Rachel Barrie at Brown-Forman The Glendronach, Benriach & Glenglassaugh Distilleries, Whisky Hall of Fame Inductee

Set in the picturesque Valley of the Brambles within the Scottish Highlands, The Glendronach Distillery has long been revered for its exceptional sherried expressions borne of the distillery’s dedication to aging their spirit in high quality Spanish sherry casks. Late last year, Glendronach unveiled its next visual chapter in a stunning worldwide launch, with updated packaging for its core range and an visual campaign that speaks of the single malt’s duality as a marriage of robust Highland spirit with a distinctive Spanish flair.

Master Blender Dr Rachel Barrie helped conceive of this bold vision. As one of the most respected living figures in the Scotch whisky industry, Dr Barrie’s journey was nothing short of remarkable. With a First Class Honours in Chemistry from Edinburgh, she embarked on a career path less travelled, joining the Scotch Whisky Research Institute at a time when not only were women a rarity in the field, but the science of whisky itself remained largely unexplored.

There, at the very forefront of whisky research, she immersed herself in the chemistry of whisky while working with the legendary Dr Jim Swan to develop new maturation techniques and identify key flavour compounds with advancements in sensory analysis. Her early work in whisky research developed techniques that continue to shape the industry today. Dr Barrie then went on to work with several iconic Scotch distilleries in every major region and helped create some of the most beloved single malts on the market while scooping up a dizzying array of accolades – most notably, she’s the first female master blender inducted into the prestigious Whisky Magazine Hall of Fame.

Today, Dr Barrie holds the position of Master Blender and Senior Leader of spirits giant Brown-Forman's three Scotch distilleries – The Glendronach, Benriach and Glenglassaugh. In this role, she crafts the unique vision and future for each of these historic brands, nurturing their individual personalities and guiding them to their full potential.

In a recent interview with 88 Bamboo, she eloquently described her role as having three beloved sons to care for. “I love them all, but I have to focus on each one at different times to make them the very best they can be.” And indeed, what distinctive qualities there are – there’s The Glendronach, with its sherry cask mastery; Benriach, known for its innovative spirit; and Glenglassaugh, carrying the unmistakable influence of its coastal home.

We talked about Dr Barrie’s multifaceted role as a Master Blender, a position that demands not only a refined palate and an intimate knowledge of whisky production, but also a talent for innovating with a sharp business acumen. We discussed how Benriach has become a canvas for experimentation, pushing the boundaries of flavour with its diverse cask maturation program and unique peating levels. We explored the profound impact of location and environment on the final character of a whisky, learning that even the most skilled Master Blender cannot replicate the distinct coastal influence imparted on Glenglassaugh.

She shared in vivid detail her vision for each of these three iconic malts with us, and also spoke with an infectious optimism about the future of Scotch whisky as a whole – leaving me incredibly excited for what’s to come in Scotch.

But let's start at the beginning, with the young Rachel Barrie’s formative years in Aberdeenshire and at the Scotch Whisky Research Institute…

Follow Dr Barrie's adventures here: @rbwhiskymaker

Follow each of Dr Barrie's beloved children: @theglendronachofficial | @benriach | @glenglassaugh

My interest in science and understanding definitely came first, and whisky became a wonderful vehicle—a way to explore the land, the sea, the air, the elements, flavour, chemistry, and people. 

88B: You’re known for the exceptional ability to marry art and science in the realm of whiskymaking. But could you share with us which came first – your interest in whisky or your love for science? How did one lead to the other, or did they develop in tandem?

You grew up in Aberdeenshire which has a rich whisky heritage. What did whisky mean to your grandmother, father and the wider community? Were there any interesting childhood experiences that influenced your early impressions of whisky?

Rachel: Whisky has always been part of my life. However, I would say, in my essence, my nature is to really understand the nature of everything. So, my interest in science, art, the universe, and everything in it definitely came first. My curiosity about the nature of everything is what drives me.

In life, whether or not there was whisky, I suppose it’s a philosophy and an approach where I have a very inquisitive mind. I want to understand the nature of my life, the universe, and the world, and whisky has been a part of that world.

The historic county of Aberdeenshire (Source: VisitScotland)

Growing up in the countryside, I learned about farming, community, art, and culture. I was a musician; I learned about science, dance, and travelled. Whisky was always around. My grandparents enjoyed whisky, but it was more about bringing people together. They probably didn’t have the same level of appreciation my father ended up having. For my grandparents, it was always something that brought people together—at Hogmanay or within the community, where people would come in, have a dram, and tell stories. That sense of community always felt very warm and inviting.

My dad, though, became very interested in single malts and started collecting them. That was in the mid-1970s—when I was just a small child—and through the 1980s. He really got into single malts at a time when they started to grow in popularity both at home and abroad. There was a big expansion in the industry in the 1970s, and that was when distilleries began to make their mark.

I was always curious about his interest, and when I went to university, I joined the Water of Life Society. We started it up and had a miniature dram every week to get to know different distilleries.

So yes, my interest in science and understanding definitely came first, and whisky became a wonderful vehicle—a way to explore the land, the sea, the air, the elements, flavour, chemistry, and people. It’s a wonderful science that helps you understand so many different things in life.

88B: If you could imagine for a second that you hadn't joined whisky companies, given your talent and scientific inclination, what other kinds of career do you imagine yourself having, and what industries could you have revolutionised?

Rachel: Life is too short to explore everything I’d want to do, but that’s why it was so difficult for me growing up to decide which avenue to take—I found everything really fascinating. I initially studied medicine, which I found quite interesting, but I was probably too creative and, in some ways, not empathetic enough to pursue it as a career. But I still find medicine fascinating.

So, I think I would have gone into some form of research—definitely research and development—where I could create something new. Whether it was a new medicine, a new perfume, new flavours, new food—just anything where I could use existing knowledge to bring something innovative to consumers.

What I really love is creating a fresh perspective on something, seeing things in a different way, and developing new products. That’s what inspires me the most: the process of research and development and bringing new ideas to life.

You would never imagine it when you taste a grain of barley – which doesn’t taste fruity at all on its own – where does the fruit come from? It's really quite remarkable how much fruitiness can be released – everything from your pears and apples to pineapples to berry fruits to every type of fruit imaginable.

88B: Fresh out of University, you’ve had an incredibly strong start in the world of whisky as you landed a role as research scientist at the prestigious Scotch Whisky Research Institute. There, you worked alongside Dr Jim Swan to develop techniques that would help numerous distilleries take their first steps towards crafting great whisky, including groundbreaking work on developing the ideal bourbon cask for maturation. You’ve said that it was here where your passion for and knowledge of whiskymaking flourished.

Could you recount and share with us any “aha!” moments during your time at the Scotch Whisky Research Institute that fundamentally changed your understanding of whisky, or moments of inspiration that validated your decision to pursue a career in whiskymaking for the next 30 years?

Rachel: So many, so many—where do I start? Dr Jim Swan was the greatest mentor. I learned so much from him, both in terms of analytics and knowledge, but also in terms of his approach. It was here that I first learned how important it was to link human sensory perception with whisky production and analytics—the science behind which compounds are key markers for creating the best whisky.

There are probably three main projects that stand out for me, each with its own “aha!” moments.

The first was looking at the estery character of new-make spirit across distilleries. Estery character—essentially the fruitiness—is crucial to the finest single malt whiskies. Unlocking the full potential of esters, the entire spectrum or “rainbow” of fruitiness, is absolutely fascinating. You would never imagine it when you taste a grain of barley – which doesn’t taste fruity at all on its own – where does the fruit come from? It's really quite remarkable how much fruitiness can be released – everything from your pears and apples to pineapples to berry fruits to every type of fruit imaginable. One of the key insights was how to unlock this fruit potential, particularly as barley varieties were being bred with higher starch content for greater alcohol yield.

Through lab experiments, I learned the importance of having clear wort during the mashing process—without having too many fatty lipids around—so that when the yeast ferments, it produces that fountain of fruit without anything holding it back.

I also learned about the influence of gravity—how much water you add to the barley in the mash, the pitching rate of the yeast, and the original gravity.

We did so many experiments to dial up the esters and discovered that while chasing higher alcohol yield by allowing more flour in the mash could give you more alcohol, but you’re not going to get the fruit. I learned about the balance—how to amplify the very finest elements of a single malt without compromising quality, while still managing the economics of production.

The second project was focused on developing the ideal bourbon cask for maturation. This involved using advanced techniques like gas chromatography, mass spectrometry, and olfactometry to dissect the composition of oak and understand how factors like air seasoning versus kiln drying impacted flavour complexity. That was a wonderful project that really highlighted the importance of taking things slowly. For instance, when oak is seasoned in the open air, the winter weather breaks down tannins while the summer heat breaks down other elements of the wood.

We also explored the effects of charring and toasting the wood, as well as seasoning the casks with bourbon before using them for Scotch whisky maturation. So that was really fascinating from analytical perspective and also a sensory perspective, to really understand the intricacies of the composition of oak.

It was also during this time, in the early 1990s, that we began studying different species of oak— nobody else was really looking at different oak species. Led by Jim Swan at the Scotch Whisky Research Institute, we looked at Quercus mongolica (Chinese oak), Japanese oak (Mizunara), Hungarian oak, German oak, and others to understand how each species influenced different flavours. That exploration was fascinating.

The third project was focused on sherry casks, and it is the one which I still apply the most in my thinking today, especially in my work with The Glendronach. In the late 1980s, the sherry industry stopped sending casks to the UK for bottling, as regulations required all sherry to be bottled in Spain to carry the name. This posed a huge challenge for the Scotch whisky industry then because, what do we do? We’re not going to get these sherry casks anymore.

We worked on the sustainability of sherry casks and ensuring that our Scotch industry could still have a sustainable quality of sherry casks moving forward without Spain shipping sherry casks over to the UK. It’s something I still have in my head very much today working at The Glendronach – applying what I learned in terms of the differences between Spanish oak, European oak, and American oak, as well as the characteristics of solera casks (which had been used multiple times in Spain) versus newly seasoned casks.

There was a lot of chemistry in understanding sherry wood maturation—its influence on colour, flavour. There’s also the overall impact on the Scotch whisky industry in the decades that followed the changes in sherry cask sales and production, and getting hold of the best sherry casks going forward.

I could go on and on, but these are the three main projects.

Some products are so incredibly successful but they have to be withdrawn because they can’t be scaled.

For example—a Madeira wood finish way back in the 1990s. It was fantastic, but because it was so difficult to source Madiera casks from such a small island, we just couldn’t get enough of them to meet demand.

88B: What does it take to be a Master Blender at a major Scotch distillery? You've spoken before about the extensive work behind the scenes in blending and the constant experimentation and refinement required.

Could you give us a glimpse into the responsibilities that fill your day? What are the most rewarding and enjoyable moments of your job?

Rachel: Every Master Blender has different experiences, but I think there are some uniting features. First, you have to be a guardian and custodian of quality. Second, you need to be an innovator and have a creative spark. Third, you must do the best you can for the business and get the most out of your inventory. And finally you must be an ambassador.

First of all, when you work in an already established company by great master blenders, you’re basically standing on the shoulders of giants. These distilleries have been around for centuries. The Glendronach, for instance, has been around since 1826, and if you think of other renowned distilleries, most of them also date back to the 19th century. They’ve developed incredible portfolios and ranges of products that can be revived. The Glendronach is way up there as one of the most revered.

The Glendronach Distillery.

So, I would say first and foremost that being a guardian and custodian of quality is absolutely paramount! This means you really have to understand the intricacies of your stock profile. I’m very lucky to be working with our spirit from the still all the way through to our tens of thousands of sherry casks maturing at The Glendronach Distillery. Our oldest cask currently dates back to 1968, so it’s basically 56 years old. I hate to say it, but that’s about the same age as me! *laughs* Being able to understand the maturing inventory and the standards of quality you need to maintain is absolutely paramount.

A top aspect of my job is really managing risk. That means making sure we don’t lose too much whisky to the angels during maturation, ensuring there’s not too much evaporation, and casks don’t leak.

We need to make sure we have great-quality casks that are going to nurture our spirit. They need to be sound—no leaks—so that we’ll have whisky to sell decades from now, whisky that could approach 56 years old or even older. I have to make sure we’re working with the very best quality wood.

Making sure the spirit quality from the still is exactly as we want it to be. A lot of time is spent nosing every spirit that goes into cask, reviewing the wood policy each year, and looking at the quality of the wood and the inventory. So being a guardian and custodian of both the wood the whisky-making process is number-one.

Number two is really being an innovator. I would say that’s where the creative spark comes in—it’s probably the part I get the most joy from. It’s about looking at our whisky and really understanding its character.

For The Glendronach, it’s about taking that Highland character and exploring its Spanish flair. How can we bring it to life? It has a flamboyance and expresses an elegance, and keeps a robust Highland character. It’s about exploring its fruitiness, developing its full-bodied character in different types of sherry casks. What works really well and allows the true nature of The Glendronach to shine? Mastering sherry casks is key here—understanding what works best, with different proportions of Pedro Ximénez, Oloroso, Solera casks, seasoned casks, or even different types of fortified wine casks.

What’s going to work really well for The Glendronach’s character and bring out its best? And, of course, with different distilleries, that process looks different. For a blender worth their weight in salt, it’s like being a professor with a classroom full of students—you’re trying to bring out the best in each distillery. It will be different for every single one of them. So you have to pay attention to each distillery in how you innovate.

For The Glendronach, it’s one approach. For Benriach, and Glenglassaugh it’s another. You will see different innovations, even though I’m ultimately exploring them all as the Master Blender for all three distilleries.

Thirdly, you have to be a good businessperson and really focus on getting the most out of your inventory. Getting the best from the wood, buying the best wood within a budget, and managing your 100,000 - 160,000 casks in the best way you can for the business.

And finally, you need to be an ambassador and an advocate. That’s another part of the role that I really enjoy. For example, last year, I got out to Singapore—particularly to talk about Glenglassaugh—when we launched the Glenglassaugh Serpentine Collection, our old and rare whiskies in January. We launched the collection at Gardens by the Bay.

This past year, I’ve been traveling more than ever before. It’s about finding the right balance: being out in the markets, listening to consumers, seeing what works in different countries, and drawing inspiration from those experiences to bring back to the distillery.

So, those are really the main aspects of being a Master Blender: a good balance of maintaining quality and custodianship, innovating, creating, having a good business head, and obviously being an ambassador for the whiskies, telling their stories to the world.

Experience is a wonderful thing; it helps you develop a clearer vision… I’d say, over the past seven or eight years of working with Brown-Forman and the three malt distilleries, I feel I now see things much more clearly.

88B: On the flip side, what are some of the most challenging aspects of blending whisky that took you years of experience to truly master?

Rachel: I learn something new every day, so I definitely haven’t mastered the art yet—I'm continuing to master the art. It’s a never-ending journey.

The challenges can vary. It’s like in any year, you’re going to face different challenges. For example, some years the challenge is not having enough whisky from certain vintages or years. You might discover a gap in the stock profile, and suddenly there’s more demand than supply. You’re left thinking, “Oh my gosh, what do I do?” In those situations, you have to manage the stock profile carefully to sustain growth while figuring out how to structure the portfolio.

The portfolio planning aspect really ties together multiple facets: the business part, the quality part, the innovation part, and the markets part. And let’s be honest—who has a crystal ball? Managing the ambiguity, uncertainty, and volatility in the marketplace is arguably one of the toughest parts of the job. It’s something that does take experience to handle.

I’ve learned—from nearly 33 years of experience, you start to see the peaks and troughs. Some products are so incredibly successful but they have to be withdrawn because they can’t be scaled.

For example—a Madeira wood finish way back in the 1990s. It was fantastic, but because it was so difficult to source Madiera casks from such a small island, we just couldn’t get enough of them to meet demand. That product had to be withdrawn because it couldn’t be scaled or sustained.

You learn from these experiences. Now, when I’m looking at the portfolio, I can make decisions more quickly about what should be a limited edition, what type of recipe can be scalable, and what could become a core expression. Those decisions are easier to make when you’ve built up experience and knowledge—understanding the availability and quality of the wood, how to manage the inventory, and how to balance the portfolio.

Yeah, but what continues to be challenging is managing supply and demand, especially considering how long it takes for whiskies to come to market. If I have an idea today, I know it might take four or five years—or even longer—for it to come to the market.

You really have to be patient. Being able to pivot and adapt to changing needs or responses to different products and channels is probably one of the greatest challenges.

One reason Glenglassaugh was likely mothballed for 20 years is because the old-school blenders—those blending for Famous Grouse, Cutty Sark, Johnnie Walker, and so on—didn’t know what to do with it. It was too distinctive, too unique. There’s no other distillery like it!

88B: Throughout your illustrious career, you have played a pivotal role crafting exceptional whiskies that make distilleries iconic. You’ve had a hand shaping many highly respected and sought-after brands with devoted followings today.

Is there a formula or a playbook to unlocking each distillery’s potential and propelling them to greater heights? When you first encounter a distillery's malt as Master Blender, how do you envision its future and decide on the direction to take? And what're the most crucial elements of this vision to convey to consumers, whether through the whisky itself or the brand's story?

Rachel: Great question! Absolutely, you’ve nailed it - it’s about having a vision. That comes more easily to some than others, I suppose, and people might have different perspectives on what it means.

Experience is a wonderful thing; it helps you develop a clearer vision. Once you can distil all the knowledge you’ve gathered into shaping the future. You have to build that foundation of knowledge and theory first. It’s very difficult to go straight to having a clear vision. Maybe some people can, but for me, it’s taken time. It’s taken years to reach the point where I can see that vision almost instantly. I’d say, over the past seven or eight years of working with Brown-Forman and the three malt distilleries, I feel I now see things much more clearly.

I think it’s a combination of understanding the place—it’s almost a sense of terroir. Knowing the place, the people, the culture, the atmosphere, the land, the geography, the spirit of the distillery. Of course, it’s also about understanding everything: from the spirit of the still to the maturing inventory. It’s about using your senses to connect all the dots and bring everything together.

The Benriach Distillery.

So, for example, with Benriach—when I was growing up, I actually did hang gliding over Benriach once before I even knew it was a distillery. I’ve got all these sensorial experiences tied to that place, and now, when I nose the whisky, I can go, “Wow, absolutely.” It connects so beautifully. Benriach, for me, is about reaching new heights. It’s the next one that I’m absolutely going to be pouring my heart into.

And you know, today, it’s actually a beautiful sunny day here—perfect for gliding. With Benriach, when I nose and taste it, it feels like a heightened sensory experience. It lifts on your palate; it glides so beautifully. It’s such a stunning Speyside style. What I will do with Benriach will be very different from what I do with The Glendronach. Benriach, for me, is much more about the atmosphere—it’s the air, the sense of being elevated, of reaching new heights. It’s like very few other distilleries in the world of whisky, creating this beautiful finesse and delicacy. For Benriach, that sense of finesse and delicacy absolutely fits the place, the feel, and the taste of the whisky. Everything about it is just so beautiful.

Whereas with Glenglassaugh, it’s completely different. I was very lucky growing up with a love for outdoor pursuits. I actually learned to surf on the beach with my dad, just a few miles up the road—about a 20-minute drive from The Glendronach. If you ever visit, you’ll discover that for yourself.

With Glenglassaugh, it’s all about the wonderful feel of the ocean—the rolling waves, the connection to the coast. Everything I do with Glenglassaugh is about amplifying that luscious, juicy tropical flavor with that crack of sea salt you can find at Sandend Bay. It’s about capturing the essence of Sandend Bay on a summer’s day. As I go through the Glenglassaugh portfolio, my approach will evolve as the stock matures—since, as you know, there was a gap in production. Right now, we have the flagship Glenglassaugh 12 Years Old, which is perfectly balanced. Then there’s Glenglassaugh Portsoy, which is deep, wild, and evocative—like being out on the open sea.

Next, we’ll be introducing a Glenglassaugh 15 Year Old, and I’ll take it in a specific direction that reflects the place, the atmosphere, and the influence of the ocean. It’s all about bringing that sense of the coast and its unique character to life.

With The Glendronach, for me, it’s all about the rich, fertile landscape—down in the Valley of the Brambles. It has this really robust, strong backbone, a solid character and base from which the sherry casks rise with incredible flair. I try to build what I’d describe as a sherry crescendo on the palate, one that delivers an incredible crescendo of flavour and a very long finish.

Everything that goes into making these three exceptional yet distinctively different distilleries is tied to the vision—the vision of the place, the atmosphere, the terroir, the flavour, and the feeling. It’s almost like having three sons. I love them all, but I have to focus on each one at different times to make them the very best they can be.

You just have to stand on the beach at Glenglassaugh and feel the elements to understand it. The ocean has such a huge influence on the whisky. There’s nothing you can do—even as a Master Blender—that can have a bigger influence than the influence of nature with Glenglassaugh!

88B: You currently shape the expressions of The Glendronach, Benriach and Glenglassaugh – three very distinct single malts. You've spoken about the importance of immersing yourself in the inventory of each distillery, taking the time to truly understand their individual DNA and refining their signature character.

What was it that you saw in The Glendronach, Benriach, and Glenglassaugh that initially drew and inspired you to take on the role of Master Blender at Brown-Forman?

When you first assumed the appointment as Master Blender and Senior Leader, how did you systematically approach the task of "getting to know" each of the single malts? What flavour patterns and nuances do you look for? And what aspects do you need to see to be sure you have obtained the full picture of each single malt’s true potential?

Rachel: Yes, well, I mean, first and foremost, the exceptional quality. Even before I joined, I knew the exceptional quality of all three distilleries. Being a whisky fan myself, they were already revered to me, and they hadn’t really been given the opportunity to be distributed widely around the world. That presented a wonderful canvas to work on.

With The Glendronach, it already had a reputation for sherry cask mastery, which is very distinctive. The opportunity to raise expectations and truly bring that sherry cask mastery to life was huge for me. It was about using all my knowledge to seek out the very best sherry casks—what I consider to be Spanish oak, particularly Pedro Ximénez (PX)—the King of Sherry. In fact, I’ve heard from Jerez that we purchase the most PX in the industry, to my knowledge.

It’s also about finding the right balance with PX and Oloroso, ensuring perfect integration of flavours, and creating a well-rounded portfolio. Sherry cask mastery is absolutely central to The Glendronach’s DNA. A big part of my work there was getting to know the stock profile deeply.

With sherry casks, you need to analyse a lot more because they can be incredibly intense in colour and flavour. Since all our whiskies are natural in colour, we need to examine them closely. I spend a lot of time analysing cask samples with the help of the team and the warehouse staff, who draw countless samples for analysis. This process is really important.

And with Benriach, I knew even before joining that there had been so many experiments conducted over the years. Benriach continued producing peated malts long after most of Speyside had stopped in 1975. Before then, peat was likely involved in most Speyside whiskies, but Benriach kept that tradition alive. They also introduced triple distillation to Speyside for the first time and built one of the most eclectic ranges of casks.

I knew Benriach would be where I could have the most creative and innovative fun, very simply. The nuances in Benriach are always more sweetie than peaty—it’s sweet, fruit-forward, almost like a patisserie. Working with such a wide variety of wine casks has been incredible fun. From Marsala to Bordeaux, wine casks from all over the world, fortified wines, and even virgin oak and different oak species—all of these allow me to bring out Benriach’s natural sweetness and even enhance the sweetness of its peat.

It’s absolutely the distillery I experiment with the most. I have the most experiments ongoing with Benriach right now, and it’s all about building on its legacy. The spirit is so accessible and versatile, with an incredible range of nuances. Honestly, Benriach probably has the most nuances of any spirit I’ve worked with. It’s like a rainbow of fruit—so many layers of fruit, malt, and oak, with added layers of smoke. You can play tunes with it, you can paint with the flavours, and you can create these beautiful, multi-layered whiskies. It’s just great fun.

And then Glenglassaugh, for me, is really all about the place. You just have to stand on the beach at Glenglassaugh and feel the elements to understand it. The ocean has such a huge influence on the whisky. There’s nothing you can do—even as a Master Blender—that can have a bigger influence than the influence of nature with Glenglassaugh! The ocean, the salinity, and that lush tropical fruit character make it unlike any other distillery.

One reason Glenglassaugh was likely mothballed for 20 years is because the old-school blenders—those blending for Famous Grouse, Cutty Sark, Johnnie Walker, and so on—didn’t know what to do with it. It was too distinctive, too unique. There’s no other distillery like it!

For me, working with Glenglassaugh is about embracing its lush, oily texture, its tropical salinity, and those incredible elements. I often find parallels between Glenglassaugh’s flavours and the food I experience in Asia—like oily fish and vibrant tropical fruits. It’s why I think Glenglassaugh is going to really grow in Asia big time; the flavours are just so beautiful, coastal.

Back in the 1980s Glenglassaugh’s owners experimented with changing the stills and altering the process, but the spirit was not for changing. It could be connected to the water, which is very mineral-rich. Or it could be the surf—Sandend Bay has the most surf of any bay in Scotland. When the surf crashes in, it releases a lot of microbiology from the sea into the atmosphere.

88B: On that note, Glenglassaugh has experienced a remarkable revival under your guidance, culminating in the incredible achievement of the Glenglassaugh Sandend being named Whisky Advocate's Whisky of the Year.

A significant part of Glenglassaugh’s identity is its coastal location near Sandend Bay which faces the North Atlantic. Now, there’s this very romantic notion amongst whisky lovers that surrounding environment imparts a distinct maritime character to the whisky – perhaps there’s something in the sea air.

But from a scientist’s perspective – how does Glenglassaugh’s geography truly influence its distinctive flavour? What specific environmental factors are at play?

Rachel: Yeah, it's a very difficult question to be definitive about. Obviously in wine they say terroir, but that's more to do with the land. For whisky, it's more the air. The invisible things that we don't tend to measure or very rarely measure. So the microflora, the microbiology of what is in the atmosphere that influences fermentation, that influences maturation. It’s very elusive and generally are not commonly studied in whisky science. What we do measure are elements like humidity in the air, temperature, and weather-related effects. Although we don't do as in-depth analysis of the microbiological elements in the air, I believe they undoubtedly play a significant role.

So even in the spirit of distil you notice Glenglassaugh’s estery character, the tropical fruit character. It’s a fascinating study as a scientist because tropical fruit is one of the most elusive character in whisky. When I worked with my Japanese counterparts, in my previous job, the Holy Grail question was, how do you get tropical fruit in your spirit? It’s something that tends to appear after long periods of maturation – 25, 30, 40, 50 years old, in Bowmore, or other distilleries at around that age.

If you've ever had the opportunity to try, which I'm very lucky to have had, you'll notice the tropical notes start to appear in whiskies that are 25 year old or older especially in distilleries that close to the coast, and certainly in some Japanese whiskies. It’s fascinating, though, that Glenglassaugh has its tropical fruit character right off the still!

I remember trying to separate the whisky into different aliquots of organic and inorganic portions for analysis. The challenge with tropical fruit notes is that you can detect them on the nose or palate, even when they exist at only parts-per-trillion levels of certain compounds. That’s so minute, it’s almost impossible to measure using analytical instrumentation.

That’s why I say it’s very difficult to fully understand it scientifically. But at Glenglassaugh, you specifically get this in the spirit right off the still. You find notes of salted caramel, pineapple, grapefruit—it’s almost like, “Where’s the malt? How can this be?” It’s just this magical essence of making single malt whisky by the ocean, in that very specific sweet spot of Sandend Bay, where this unique character appears.

Back in the 1980s Glenglassaugh’s owners experimented with changing the stills and altering the process, but the spirit was not for changing. It could be connected to the water, which is very mineral-rich. Or it could be the surf—Sandend Bay has the most surf of any bay in Scotland. When the surf crashes in, it releases a lot of microbiology from the sea into the atmosphere. This, in turn, could influence the fermentation process, which I find fascinating. It’s similar to how soy production uses a culture containing aspergillus to amplify the salinity in the soy’s flavour. Some of the microflora released from the ocean might be creating a similar effect here. From a science perspective, it blows my mind to work this out. When you taste Glenglassaugh, you can actually feel the salinity in your mouth, but you can’t detect sodium chloride through analysis.

88B: Back in the 1980s and 1990s, the Scotch industry's understanding of the science behind whisky maturation, cask influence and flavour development must have been quite different from today. 

As someone who witnessed and contributed to this evolution since the 1990s, could you tell us how has the industry's understanding evolved over the years? What were the prevailing beliefs in the 1980s and 90s that have been challenged or refined since? Are there any misconceptions that persist today?

Rachel: The Scotch Whisky Research Institute has been around for about 50 years now. It was established in the 1970s, just as the industry was beginning to grow. But even in the 70s and 80s, as malt distilleries started becoming more prominent and gaining global recognition, there wasn’t really much focus on describing flavour in detail.

The Scotch Whisky Research Institute where Dr Barrie spent her formative years. (Source: Ross, Fraser, McLean)

Back in the 80s, there wasn’t a solid understanding of how casks influenced the whisky. For instance, there wasn’t much awareness that a cask could impart different levels of vanilla, or that the interaction between the spirit, the tannins from the wood, and the copper during maturation could create these complex, elegant notes—like a minty top note, that wonderful finesse, or even rancio notes. Where those elements came from wasn’t well understood.

It wasn’t until the late 80s and into the 90s that the focus of Scotch whisky research shifted more toward understanding the chemistry. This allowed blenders to fine-tune or perfect the spirit to deliver better quality. For example, techniques like gas chromatography and olfactometry became invaluable tools. With olfactometry, you can dissect the whisky by isolating its aroma compounds—so you might detect vanilla, identify the peak on a chromatogram, and understand its chemical composition.

However, there are still things that remain elusive. Tropical fruit, for example, doesn’t show up on the trace—you can smell it, but you don’t see anything measurable. It’s one of the mysteries that still exists.

Fortunately, the human nose remains, and will hopefully always be, the final arbiter of quality. As much as we have AI and robotics, I don’t think they will ever – or at least in my lifetime - replace human perception when it comes to tasting whisky.

88B: The Glendronach Distillery has been a cornerstone of the Scotch single malt industry, standing as one of Scotland’s oldest registered distillery, and is renowned for its mastery of Sherry cask maturation. Recently, The Glendronach has undergone a revitalisation with a relaunch of its core expressions, featuring updated packaging and a captivating campaign in collaboration with renowned photographer Rankin to highlight the distillery's Highland spirit and Spanish flair.

As we approach the momentous 200^th anniversary of The Glendronach Distillery, could you share with us what The Glendronach represents to you personally, what are some key milestones in its history that have contributed to its success and what is your vision for The Glendronach’s future? Also, can fans anticipate any special releases to commemorate this milestone?

Rachel: Absolutely. I mean, the flagship whisky is The Glendronach 12 Years Old, which you know well—it’s the one I spend the most time on. It’s our cornerstone expression, and we produce the most of it. Every batch is made up of around 74 sherry casks, and every single one has to be checked. Because it’s a natural colour product, it’s essential to ensure the nuances of colour and flavour are perfectly balanced.

The balance between the distillery’s Highland character and its Spanish flair is something that’s difficult to put into words, but for me, it’s about how the whisky lifts on the palate—it’s like it rises up out of the valley. You have the robust structure of a true Highland style whisky. In my opinion, The Glendronach represents the most original Highland style of any distillery, with its earthiness, depth, and strong backbone.

Then there’s the Spanish flair, brought in by the Spanish oak casks—Pedro Ximénez and Oloroso. Together, they create a duality of character: a crescendo of flavour that lifts the palate with elegance, full body. There’s a real counterpoise to The Glendronach which Rankin really picked up with the filming – when he sensed this earthiness, this very traditional highland feel. It’s like being in an ancient castle or old farmyard. He really captured the whisky’s elegance, its complexity, its balance of top notes and base notes. The colour, backbone, earthiness and strength of character.

Many of the most successful luxury brands of all time are timeless. They are absolutely timeless in their elegance and in their ability to have so many touch points.

If you’re a connoisseur, you’re going to love The Glendronach for its richness of character and its long, richly rewarding finish. It just goes on and on, like a crescendo of flavour. If you’re new to The Glendronach, you’ll likely be captivated by its elegance or perhaps its beauty and flamboyance. Wherever you’re coming from, this whisky offers something aspirational, yet it’s also got real depth of character. That’s what helps it stand out and raises expectations in the world of whisky. It’s about mastering that duality—that is so true to the Highlands and so true to Spain as well. We’re committed to staying true to this duality.

Spanish oak, in particular, has this duality too, which I love. It gives you the elegance and tannins in perfect harmony. All of these elements contribute to The Glendronach’s rich story that captivates both newcomers and connoisseurs alike.

88B: Benriach Distillery is known for its luscious fruit-forward spirit character, although beyond its base spirit, Benriach has had a longstanding ethos of innovation, something of a playground for creativity in whisky making. This is evident in its diverse range of cask finishes, its three distinct distillation styles (classic, peated, triple distilled), and its recent revival of traditional floor malting.

You have described your creative process at Benriach as highly iterative, involving perpetual experimentation and refinement, that the process often generates more questions than answers. That process sounds really intriguing!

Rachel: For me, Benriach is arguably the most beautifully balanced of all single malts. It’s just so beautifully balanced—it glides on your palate. You get this exquisite balance between the fruit, malt, and oak. Nothing dominates or overpowers the others.

I find that the combination of casks at Benriach creates something that transcends each individual cask—it takes the whisky to a place that feels uniquely Benriach. There are so many different casks to work with, and each one is like having a box of chocolates. I particularly love Marsala casks. They’re so beautifully sweet and bring out Benriach’s character, especially in The Smoky Twelve with Marsala—it was an absolute revelation to me. It’s always more sweetie than peaty.

The bourbon casks at Benriach are probably the truest, most authentic representation of a Speyside single malt I’ve ever come across. They deliver this beautiful balance of vanilla, orchard fruits, a touch of honey, and the creaminess of the malt. It’s just exquisite.

Then, layering on additional elements—like a touch of spice from American virgin oak or the sweetness of Marsala—adds even more depth. Each cask adds a new colour to this rich tapestry, creating something that’s wonderfully multi-layered and unique.

88B: Do you have any interesting anecdotes or stories about the experimentation process at Benriach? Are there any examples of "happy accidents" or experiments at Benriach that yielded surprisingly successful results?

Rachel: I’m always exploring different things. At the moment, it’s like a world of possibilities with Benriach—let’s put it that way. I’ve got quite a few interesting oak species maturing right now from all over the world. Some are from Asia, some from South America, and, of course, from Europe and North America. Essentially, I’ve taken the world of oak and started experimenting with species from across the globe.

At the same time, I’m exploring wine casks from various regions. While I’m working with oak from South America, I’m also looking at South American wines or spirits to see how they might combine with our whisky or inspire limited-edition expressions. So there are lots of fun projects in the works for future limited editions.

As for experimentation, I’m working with all kinds of things—different oak species, different wine casks, and even different heat treatments for the oak. For example, I’ve been experimenting with volcanic rock and other techniques to see how they influence the casks. There are no bounds to what we can try, though we always stay true to the core principles of whisky-making: it must be made with malted barley, distilled in pot stills, matured for at least three years, and aged in oak.

Within those boundaries, we’re really pushing the limits of experimentation, and it’s just so much fun.

88B: Dr Barrie, you’ve achieved so much throughout your career. Your dedication to understanding the science behind Scotch whisky production has deepened our collective knowledge and pushed the boundaries of what's possible. You’ve created some of the world's finest whiskies and worked with so many iconic distilleries. You’ve blazed a trail for women in whisky, and indeed today we’re seeing more and more women occupy important roles in the whisky and drinks industry. It’s safe to say your contributions would leave the Scotch whisky industry in a much better place than when you entered it!

Looking back on your career in both whiskymaking and research, could you share with us some of the personal highlights of your career that have meant the most to you? What advice would you give to encourage your younger self, the chemistry student with a budding interest in whisky?

Rachel: I always think the best is yet to come. It’s difficult for me to look back because I’m always looking forward. I’m a very forward thinker. I carry all my learnings in my head, but I always know there’s more to learn.

In terms of highlights, it’s really the whole journey—it’s the sum of all the experiences that’s truly the highlight of my career. Being given the opportunity to sample 170,000 casks over the years, each of which has played a little part in the “jigsaw” of my mind. That richness of experience is probably the highlight of my career. I can’t pick just one moment because it’s the sum of all of it together, the rich experience that has made the difference.

I’ve been fortunate to work with almost every distillery in Scotland at some point. When I worked with the Scotch Malt Whisky Society and had the chance to get to know nearly every distillery. I’ve worked with distilleries in every region in Scotland—Glenmorangie in the Highlands; three distilleries on Islay: Bowmore, Laphroaig, and Ardbeg; Auchentoshan in the Lowlands; and in Speyside, Glen Moray, Benriach, Glen Garioch, Ardmore, and now The Glendronach. Deep-diving into the chemistry and spirit of each region and distillery has been a real highlight of my career.

So, for me, the journey itself is the highlight. It’s greater than the sum of all its parts, and it’s greater than any one moment or experience. I can’t pick just one thing because it’s so much more than one experience. I also live in the present, and I’m always looking to the future. That’s who I am. The best is yet to come. My highlight is what I’m creating now—the releases for next year, the year after, and the year after that. It’s what I’m working on today.

In terms of advice: just keep learning, keep discovering. Use your nose—you can never smell enough whisky! Use your senses, keep developing them, and think deeply about what you’re experiencing. Connect what you taste to where the flavours come from, and always seek to understand those connections.

Dr Barrie unveiling the Benriach 50 in Hamburg, Germany.

Travel is important too. Get to know the science, learn about flavour, explore terroir, and understand spirits from around the world. It’s about embracing the abundance of the journey and the fulfilment it brings. By keeping an open mind and being curious about flavour, it will make the journey so much richer. And by doing so, you’ll also have so much more to contribute to the craft of whisky-making.

Connect with people around the world—this is something I’ve found invaluable. I often go to the TFWA (Tax Free World Association) travel retail show in Singapore, which I believe is the largest in the world. I meet so many people there and learn so much from the whisky community—it’s such a wonderful, inspiring group to be part of.

88B: Do you believe there are still big questions to answer or breakthroughs waiting in the science of Scotch whisky production? What is the next big area of innovation in Scotch whisky that you find particularly exciting?

What are your hopes for the future of Scotch whisky and what kind of legacy do you hope to see the industry leave for the generations to come? 

Rachel: I think there’s been incredible growth in the whisky industry in recent years, and with so many regions of the world now producing whisky, it’s helped to raise global awareness of the category. Looking into the crystal ball, I believe the best Scotch single malts will continue to raise the bar in every way—whether it’s in their complexity, balance, taste, storytelling, packaging, or the overall experience.

It feels like we’re just at the start of a journey toward true mastery of single malt Scotch. I see Scotch whisky mastering the category and continuing to lead the field globally. I think the industry will keep pushing boundaries and raising expectations. The quality will just keep getting better and better, which means consumers have so much to look forward to—whether it’s in the taste experience, the storytelling, or even the experience of visiting a distillery.

There’s been huge investment in creating incredible visitor experiences across Scotland. At The Glendronach, for instance, we’re coming up to our 200th anniversary in 2026. This year, we’re expanding the distillery, and we’re developing an entirely new visitor experience to open in the middle of 2026. When people come to visit, it’s going to have a real wow factor—something that will exceed expectations.

There’s so much to look forward to, and the best is yet to come.

We’re incredibly privileged to share our conversation with Dr Rachel Barrie who has had a hand in shaping the Scotch industry as we know it today. We thank Dr Barrie and the Brown-Forman team once again for making this interview possible. 

@CharsiuCharlie