The results of a peer-reviewed paper into terroir in whisky funded by Waterford in Ireland have just been announced. It seems that where barley is grown does indeed have a noticeable effect on the chemical composition and taste of the resulting spirit. Here’s the full story:

It’s one of the most contested questions in whisky, does where the barley is grown have a noticeable effect on the finished product? Many in the Scotch whisky business have said no but Mark Reynier formerly at Bruichladdich on Islay and now Waterford in Ireland has always insisted it does. The first bottlings from Waterford we tried last year seemed to bear (or should that be bere this out?) this out, now a study published in Foods journal carried out by Oregon State University adds scientific weight to Reynier’s argument. 

Research funded by the Waterford Distillery

The research, which was funded by the Waterford Distillery, compared two barley varieties, Olympus and Laureate, grown on two farms in 2017 and 2018: Athy, Co. Kildare and Bunclody, Co. Wexford. 

Waterford Terroir in whisky infographic

There’s no need to read the whole article with this handy infographic

Each sample of barley was malted and distilled in a laboratory to produce 32 different whisky distillate samples. These were then analysed using gas chromatography–mass spectrometry–olfactometry (GC-MS-O) as well as tasted by a team of sensory experts.

Dr Dustin Herb, lead researcher and post-doctoral research at Oregon State University, explained: “This interdisciplinary study investigated the basis of terroir by examining the genetic, physiological, and metabolic mechanisms of barley contributing to whisky flavour. Using standardised malting and distillation protocols, we preserved distinct flavours associated with the testing environments and observed year-to-year variations, indicating that terroir is a significant contributor to whisky flavour.”

Another one of the international team involved, Professor Kieran Kilcawley, principal research officer at Teagasc (part of the Irish department of agriculture) added: “We utilised gas chromatography olfactometry which enabled us to discern the most important volatile aroma compounds that impacted sensory perception of the new make spirit. This research not only highlights the importance of terroir, but also enhances our knowledge of key aroma compounds in whisky.”

Noticeable differences in the new make spirit

The Athy farm’s terroir consists of limestone soil with high levels of calcium, magnesium and molybdenum, and a warmer and drier microclimate. According to the press release the new make “was characterised by toasted almond notes, and a malty, biscuity, oily finish.”

Bunclody farm, in contrast, has shale and slate bedrock containing high levels of iron, copper, and manganese with more volatile weather from its coastal position. The new make was reported to be “lighter and floral, with a flavour of fresh fruitiness.”

The tests discovered over 42 different flavour compounds, half of which were directly influenced by where the barley was grown.

When we asked about how much flavour variation may have come from different barley strains, we received the following reply from Waterford: “There was some flavour variance due to variety but the effect of environment was greater. We surmised that the low variance in variety maybe due to the fact that the varieties chosen share a similar genetic heritage. Many modern barley varieties are grown for yield and disease resistance rather than flavour. This is why Waterford’s starting to look at older barley varieties as potentially they may be more flavoursome.”


The night is dark and full of terroirs

Mark Reynier (above), founder and CEO of Waterford, was bullish about the results: “Barley is what makes single malt whisky the most flavoursome spirit in the world. This study proves that barley’s flavours are influenced by where it is grown, meaning – like wine and Cognac – whisky’s taste is terroir-driven. Critics claimed any terroir effect would be destroyed by the whisky-making process, saying there is no scientific evidence to prove that terroir even exists. Well, there is now.”

It certainly looks promising for Reynier but it’s early days for the project. The first stage of the research only looked at new make spirit. The second stage will look at what differences survive the maturation process and is due to be published in 2022. The debate isn’t over yet.