A Pattern Emerges
In the early 1980s, PSWR member companies asked Jim Swan's team to investigate a pattern in their mature whiskies. The analytical tools developed throughout the 1970s revealed measurable reductions in compounds extracted from oak during maturation.
These were not minor fluctuations. The data showed consistent trends. The team's sensory science capabilities demonstrated that these chemical changes correlated directly with what trained panels detected in the whisky.
The distilleries had not changed. The barley remained the same. Yet the whisky emerging from casks showed differences. The focus turned to wood quality and cask supply.
Scotland's Supply Dependency
The investigation revealed the extent of the Scottish whisky industry's dependency on a single source for maturation casks. Over decades, this dependency had developed gradually. The industry had shifted from manufacturing casks to its own specifications to accepting whatever bourbon production made available.
Scotland had limited domestic cooperage capacity, reduced control over cask specifications, and questions about quality in available barrels.
What factors were affecting wood quality? How had industry changes influenced cask availability and performance?
Autumn 1986: Investigation at the Source
Jim Swan's presentation to the PSWR board combined chemical data, sensory confirmation, and statistical analysis. The board agreed to send a delegation to America. With additional funding from government sources, a research team travelled to American forests, stave mills, and cooperages.
The Bourbon industry was experiencing contraction whilst demand from Scotland and other markets remained steady. The delegation documented changes in forestry practices, processing methods, and cooperage operations.
Observed Industry Patterns
At one former bourbon distillery, the delegation encountered a case study in quality degradation. A brand that had previously commanded premium prices and consumer loyalty had ceased production. Personnel attributed the decline to cumulative modifications in production practices.
In spirits, reputation built over generations can be affected within years through quality compromises. Once consumers detect declining quality, purchasing behaviour changes. The parallel to Scotch whisky's situation required consideration.
How does one maintain quality when supply chains contract? Which factors prove most significant for maturation outcomes?
From Investigation to Specialisation
Jim Swan returned to Scotland with detailed understanding of the factors affecting wood supply. The 1986 visit marked a significant point in his career. The investigation demonstrated that addressing the wood quality challenge required deeper understanding of how oak wood influenced final whisky character.
He chose to focus on wood maturation science. His investigation would develop understanding of the mechanisms at work during maturation and how these were affected by wood, environment, and spirit quality—a framework connecting aspects of the maturation process.
Further Information
The investigation is documented in the forthcoming book about Dr Jim Swan's work in whisky science. The account includes findings from the American visit, the analytical techniques employed, and the development of approaches to understanding wood maturation.