The Secrets of Liquid Sunshine

The seasoned wine quaffers among you will already know the importance of “terroir” when it comes to the distinct flavors found in your glass. But whiskey is not wine – and here, the impact of soil, climate, and sunlight has been largely overlooked. 

Now, a team of industry and public sector researchers (presumably whiskey lovers) decided to investigate whether the environment in which barley is grown can contribute to the unique flavor components of new-make (unmatured) single malt whiskey. To do this, they used two different “analytical” methods: i) a sensory panel, consisting of six highly-trained whiskey enthusiasts who evaluated the spirit based on “holistic aroma and taste perception” and ii) GC olfactometry (GCO).

“In GCO, molecules within the spirit samples are separated via vapor point and polarity, then simultaneously identified via molecular fragment shape and abundance using MS,” says Dustin Herb, co-author of the paper. “The molecules are then further characterized by another trained panel who assign an aroma and intensity.” 

After much separating, sniffing and tasting, the team found that barley variety certainly plays a key role in the flavor of single malt whiskey, but so does the terroir – when and where the grain is grown and how it is managed by individual farmers. Indeed, chemometric analysis of both datasets suggested that the environment and season had more of an effect on aromatic sensory perception than variety alone.

The take home? “Using a terroir model for whisky production creates a niche among local and regional distillers to capitalize on the individual ‘terroir’ of their local environments – soil types, microclimates, and crop management practices,” says Herb. “Furthermore, by placing a value-added label on the barley, farmers are given a profitable rotational crop to help break prevailing monocultures while increasing weed suppression, disrupting pathogen and pest cycles, improving soil health, and overall benefiting subsequent crops.”

The team plan to further their research by validating their findings under commercial production scale conditions and looking at other factors that could impact whiskey flavor. 

The seasoned wine quaffers among you will already know the importance of “terroir” when it comes to the distinct flavors found in your glass. But whiskey is not wine – and here, the impact of soil, climate, and sunlight has been largely overlooked. 

But a team of industry and public sector researchers (presumably whiskey lovers) decided to investigate whether the environment in which barley is grown can contribute to the unique flavor components of new-make (unmatured) single malt whiskey. To do this, they used two different “analytical” methods: i) a sensory panel, consisting of six highly-trained whiskey enthusiasts who evaluated the spirit based on “holistic aroma and taste perception” and ii) gas chromatography olfactometry (GCO).

“In GCO, molecules within the spirit samples are separated via vapor point and polarity, then simultaneously identified via molecular fragment shape and abundance using MS,” says Dustin Herb, co-author of the paper. “The molecules are then further characterized by another trained panel who assign an aroma and intensity.” 

After much separating, sniffing and tasting, the team found that barley variety certainly plays a key role in the flavor of single malt whiskey, but so does the terroir – when and where the grain is grown and how it is managed by individual farmers. Indeed, chemometric analysis of both datasets suggested that the environment and season had more of an effect on aromatic sensory perception than variety alone.

The take home? “Using a terroir model for whisky production creates a niche among local and regional distillers to capitalize on the individual ‘terroir’ of their local environments – soil types, microclimates, and crop management practices,” says Herb. “Furthermore, by placing a value-added label on the barley, farmers are given a profitable rotational crop to help break prevailing monocultures while increasing weed suppression, disrupting pathogen and pest cycles, improving soil health, and overall benefiting subsequent crops.”

The team plan to further their research by validating their findings under commercial production scale conditions and looking at other factors that could impact whiskey flavor.