Herds of grazing gelada monkeys in the Ethiopian planes allow wolves to openly mingle, despite, in nature’s terms, being an all-inclusive buffet to the predators. However, rather than eat the monkeys the wolves kill the rodents grazing among the herd and it is suggested the return for the monkeys is that the wolves act as olfactory sentinels to warn off even bigger predators. Symbiotic relationships are one of nature’s great wonders – a mutually beneficial understanding developed over thousands of years. While it may not be as old, the relationship between sherry and whisky is comparable to that of the wolves and monkeys.
Over the past 25 years, single malt whiskies have found value in using ex-sherry casks for maturation, while sherry houses have garnered a secondary income from the sales of their precious casks. However, what started out as a love affair with single malt Scotch brands has blown up into a global frenzy. The reason is simple – new whisky distilleries around the world want more sherry casks, while sales of sherry simultaneously continue to dwindle. That’s an unsustainable model – if the number of rodents declined, then the monkeys would be next on the wolves’ menu.
“There are so many new distilleries that sourcing the right casks is becoming seriously difficult,” says Kieran Healey-Ryder, head of whisky discovery at Whyte & Mackay. “We have extraordinarily close relationships with sherry producers so that we can dictate the flavour profiles of the wines being produced in order to achieve the casks we want, which in turn produces the whiskies we want. We then visit Jerez twice a year to check on progress.”
Each of the brands in the Whyte & Mackay portfolio of single malts – Tamnavulin, Jura, Fettercairn and The Dalmore – has been influenced by sherry casks over the years and the company enjoys one of the longest-running partnerships with Gonzales Byass, producer of Tío Pepe.
In Taiwan, Kavalan Single Malt Whisky launched in 2005 and has become a specialist in sherry cask single malts. R&D director and senior blender Zerose Yang also emphasises the importance of long-term relationships. “The supply of traditional solera-aged sherry casks has become increasingly limited due to declining sherry consumption and surging global demand from the whisky industry. These casks are harder to come by and we are fully aware of the challenge this presents,” says Yang.
“Fortunately, Kavalan chief executive YT Lee had the foresight to develop a long-term strategy. We have been working closely with our partners to ensure a sustainable supply of quality casks while expanding a product roadmap that not only aligns with evolving market trends but also reinforces the core of our brand identity.
“We source our casks from multiple bodegas that are certified by the Consejo Regulador of the sherry region. These bodegas comply with official guidelines for cask preparation and sherry maturation. Our team maintains close communication and performs regular site visits to ensure quality and consistency.”
Flavour first
When it comes to selecting the sherry casks, Healey-Ryder says: “The choice is always dictated primarily by flavour. It’s not about the casks themselves, but the wines the cask previously held which provide this flavour.
“We also don’t talk about new make enough as an industry, but actually it’s 50% of the resulting flavour. However, it needs to complement the wines used in the casks. If we took Fettercairn’s light and tropical whisky and a rich port wine, the whisky would be overpowered.
“Whereas with The Dalmore the new make is notoriously thick, which means you have about seven years in the barrel before the whisky starts to benefit. We can also use what Gonzalez Byass calls its Matusalem recipe, which is a cask drenched in 30-year-old sherry. We actually have about a pint of the sherry left in the cask for its journey to Scotland so that it’s as fresh as possible for the new make.”
In Taiwan, there are other factors to consider, such as its subtropical climate, where higher humidity and temperature shifts accelerate maturation. Yang says: “We are especially mindful of selecting casks that can harmonise with local conditions. We look for wood that can not only withstand these dynamics but also contribute depth and balance to the resulting whisky.
“We pay special attention to factors such as wood porosity and thickness, which can greatly influence aroma and flavour development. Rather than relying on assumptions, we actively test how different sherry cask types perform under local conditions. Over time, this has enabled us to build a climate-specific cask performance model that guides our selection and maturation strategy in the future.”
As the demand for rare sherry casks increases, the practice of seasoning – ageing barrels in sherry for a couple of years specifically to sell on – has become financially significant for the sherry industry. It not only turns over revenue for sherry bodegas, but services the bulk of whisky brands around the world wanting to produce a sherry cask finish at an accessible price point.
“On some other brands [than The Dalmore] we will experiment with techniques to produce the same flavour and quality but by being more efficient in the production method, including the casks,” says Healey-Ryder.
Downsides
Established brands such as Kavalan and The Dalmore may have deep-rooted relationships with Jerez and respect the region, but the obsession by cheaper brands to still use sherry as a selling point is a problem.
“My greatest concern is that the industry devalues sherry, because some of the wines produced in Jerez are the very best in the world,” says Healey-Ryder. “If we begin to find ways of reducing the cost of whisky in Scotland or anywhere outside Spain, then that revenue will be lost somewhere down the supply chain, which is dangerous for the sherry industry. Whereas if you buy a bottle of The Dalmore in Shanghai, a portion of that money is being given to a farmer in Jerez.
“The other concern is that brands all over the world using sherry in their description would suggest to consumers that all sherry is the same, which is criminal.”
For Kavalan’s Yang, exploring the diversity of different sherry types is intrinsic to the brand’s development. “Right now, we work with seven types of sherry casks across our whiskies, including fully sherry cask-matured cask strength expressions. This gives us a solid foundation while still letting us try new things.”
A lack of consumer knowledge mixed with limited communication is another potential issue for the sherry industry, as Healey-Ryder continues: “Retailers are causing a problem. They dial everything down to a few soundbites to easily connect with consumers, but this again suggests that all sherry tastes the same and therefore all sherry cask whisky tastes the same.”
The other fallout from simplifying the sherry industry on whisky labels is that consumers will never understand the difference between a single malt aged in rare 30-year-old Matusalem casks, for example, or a seasoned barrel. The focus will remain on the age of the whisky and the knowledge it’s been ‘aged in sherry’.
