STUART Harvey, the Master Blender at Inver House Distillers, is a man who truly knows his craft. Over the years, the whisky wizard has helped the distillery company create numerous single malts and blended whiskies for their various brands, some of which have won awards. These whisky brands include Old Pulteney, Balblair, Knockdhu, Speyburn and Balmenach.
A conversation with Harvey about whisky is akin to a conversation with a perfumer, as he regularly delves into discussing the complex accords of an expression. This is a man whose nose knows and he admits using a perfumer’s terms to nose whiskies and describe them.
“You have to have good sensory expertise and be able to describe the top, middle and end notes. It’s a very similar process – when I’m nosing a whisky, I always nose it at natural strength and then put in the descriptors for that,” he explains.
“You also get more definite aromas as you reduce strength. Sometimes, I put a splash of water in to take it down to maybe 20% to see how the balance changes in the whisky. This process is repeated a few times just to get all the different characteristics that you can detect in a whisky. I always write down in order what hits me first and it does change as I go back and forth,” he expounds.
Ayrshire-born Harvey has put his biochemistry degree and knowledge to full use since joining the brewing industry in 1987, the same year he graduated from the University of Strathclyde. It was his ideal job and Harvey made the move from Glasgow to London during London’s lager boom years. For two and a half years, he learnt everything he could about the whole brewing process.
“At that time, I was a big beer fan. I thought moving to make beers was utopia,” he says.
“It was good fun. There were a lot of franchised beers – we were brewing Carlsberg, Holsten, Molson … you name it. It was all the big lagers in the day. That was also the start of Budweiser in the UK; we ended up brewing that at the Mortlake Brewery where I worked.”
“I learnt the different styles for different beers, the different hops, how the ale kind of develops flavour so that’s where I started my sensory training. Tasting time was every day at 12 o’clock. You have six or eight beers and you get trained to nose, taste and describe them. That’s where my sensory skills started to develop – it wasn’t just drinking beers but appreciating and rating them, which I enjoyed,” Harvey recalls.
He later moved to Halifax, Yorkshire where he juggled working at Webster’s Brewery while studying for brewing exams to become an associate member of the Institute of Brewing. He then went on to study and complete the Master Brewer diploma from the IoB.
Harvey had spent seven and a half years in the brewing industry when the opportunity arose for him to join the whisky industry and move back to Scotland.
“It was just too good an opportunity to turn down. I don’t regret it. The whisky industry has been fantastic from 1995 through to present day. It’s all really enjoyable and you continue to learn every day and that’s what I think fascinated me,” Harvey says.
At the time of this interview, Harvey was in Kuala Lumpur to promote three expressions from Speyburn single malt Scotch whisky – the 10-year-old, 15-year-old and 18-year-old.
The Speyburn 10 Year Old is fresh and clean with a hint of lemon on the nose and flavour-wise, is medium-bodied with hints of toffee and butterscotch and a long sweet finish. The Speyburn 15 Year Old, on other hand, offers hints of rich dark chocolate with spicy notes of raisin, zesty citrus fruits and vanilla on the nose. On the palate, it tastes of oranges, toffee, vanilla and leather, all wrapped together with a gentle spice. The 15 Year Old’s long-lasting finish has a warming spice which is sweet and creamy.
The dark golden Speyburn 18 Year Old is a medley of sweet scents and rich flavours. A quick nose reveals notes of sweet toffee, sugared almonds and chunky tropical fruit with hints of caramelised sugar and candied apples layered with a slight honeyed smokiness. Taste-wise, expect creamy dark chocolate, toffee, some gentle oak spiciness and a touch of citrus which all give way to a long, slightly smoky finish with a bittersweet edge.
According to Harvey, the leather comes from the new make spirit via the worm tubs. Sulphur compounds are the ones that tend to move to give the toffee and butterscotch aromas, after interacting with the charcoal layer on the ex-bourbon barrels. The esters that give the orange, lemon and floral fragrant aromas are from the fermentation.
“If you make a really bright clear wash, then your esters are much better during fermentation. That was critical when you were making beer. It just had to be completely bright or you just didn’t collect it. You would recirculate it just to make sure it’s bright. It just takes a little bit of trub – the fatty stuff that you trap and the bed – to get through and it kill your esters completely,” explains Harvey.
“When you’re brewing a lager, it’s like you have a production manual and there is a fixed way of brewing it – you do not change anything. With whisky, you find different things every day. You get casks and you nose them and you just don’t know what you’re going to find sometimes. They can be quite fascinating because obviously, you’re looking at casks that were produced 18, 20 years ago. With whisky, you can’t define it as closely as you can beer,” he elaborates.
“The stills hold many unknowns with them, like perfumes. Some of the compounds are so tiny or miniscule that you’ll never detect some things chemically. It’s all in your nose or your palate. That’s the most important piece of equipment based on the sensory side of things. What I find fantastic about whisky is that you’ll never ever define every single compound that’s in single malt whisky.”
Aside from nosing and tasting the whiskies, Harvey is also responsible for buying the casks they mature in.
The whisky industry is currently seeing big growth in single cask expressions. Harvey reveals that Inver House has been picking out casks for single casks bottlings and are looking to do around 100 casks a year.
It depends on what we find. We have some 2004 casks that we’ve found that are really nice but we’ve also been bottling some 1996 casks that we think are really good. It all depends on the market and how receptive they are to single casks. Speyburn is targeting malt whisky aficionados who prefer “something straight from the cask going straight into the bottle.”
A bourbon barrel could produce 200 to 250 bottles where a 200L barrel would produce 140L to 150L after maturation, losing strength and the angels’ share. Harvey says that it’s a rare thing that something does not go right after the expected maturation period. This is where experience comes in. Ensuring tight control in cask quality means not getting the inferior quality that they used to get from the matured casks from Spain back in the day. That is why Inver House pays the prices it does for its casks – this assures them consistency and quality without surprises after 12 years.
“That’s where you have to be very careful. Buying mature casks from Spain was mainly unreliable because they could sell you casks that had been in a bodega for 200 years and were basically totally inert with not much reaction potential left in them. That’s why as a group, we basically pay the cooperages in Spain to manufacture new casks. We set the specifications for them – the size and thickness of the staves, and toasting time – so quality in the cask is there,” explains Harvey.
According to Harvey, the way the different trees grow affect how they are prepared and burnt to get the charcoal onto the wood. American Oak grows very straight and very slowly which gives it a tight grain – it has to be burnt at 600°C to open it up. Spanish Oak, on the other hand, grows in Galicia in extreme conditions – very hot summers and very cold winters making the oak tree grow twisted and gnarled. When the wood is finally cut, there is a lot of wastage because those knotted sections cannot be used to make staves. While this may give the wood a looser grain for it to be toasted at 200°C, the overall wastage results in Spanish Oak being a lot more expensive than American Oak.
“Spanish Oak has a more open structure, that’s why you want to just toast it, to gently shape the cask. The wood also has much higher sugar and tannin levels so it has to be treated gently – we don’t want too much tannin coming into the whisky or it can become very bitter and astringent,” Harvey expounds.
“When we produce the 15 Year Old, we keep it in the Spanish Oak for about two years – I’ve discovered that gives it a nice balance for it to spend 13 years in the American Oak, and then two years in the Spanish Oak. You still get the new make character and the floral fragrant aromas. The toffee, vanilla and honey come from the American Oak while the spicy chocolate, raisins and Christmas cake come from the Spanish Oak. To me, the 15 has a nice balance,” he says.