Â鶹ÒùÔº

Scientists have discovered that juniper berries—the key botanical giving gin its distinctive taste—vary dramatically depending on where they're grown and weather conditions at harvest, potentially affecting the U.K.'s favorite spirit.

In a new study from Heriot-Watt's International Center for Brewing and Distilling, researchers found that changing weather patterns may be altering the flavor compounds in juniper berries, gin's essential ingredient.

Matthew Pauley, assistant professor at the ICBD, said, "A wet harvest year can reduce the total volatile compounds in juniper by about 12% compared to a dry year.

"This has direct implications for the sensory characteristics that make gin taste like gin."

The findings are in the Journal of the Institute of Brewing.

Regional differences matter

The study examined juniper berries from seven different regions across Europe, including Albania, Bosnia, Macedonia, Montenegro, Serbia, Kosovo, and Italy.

The regions are a mixture of established, major producers of juniper berries for gin makers and emerging regions.

Pauley said, "Just as wine enthusiasts talk about 'terroir'—the influence of geography on grape flavors—we're seeing that juniper has its own regional signature."

Each region produced berries with distinct chemical profiles, with some compounds showing high variability between locations. These differences could affect the woody, resinous, citrus, and floral notes in the final gin product.

Climate impact

Weather conditions during harvest years showed significant variations, with 2017 being notably wetter than 2018. The researchers found that increased rainfall necessitated longer drying periods for the berries, affecting their chemical composition.

Professor Annie Hill, the study's supervisor, said, "The least water-soluble compounds are most affected by post-harvest drying.

"For distillers, this means the flavor profile can shift depending on the harvest conditions.

"For a multibillion-pound industry, which is increasingly focused on consistency and quality for its discerning consumers, this represents a risk."

What this means for your G&T

The findings suggest that subtle variations in gin might be down to changing climate conditions affecting juniper supplies.

Premium gin producers typically source juniper from specific regions to maintain a consistent "house style." As climate patterns shift, distillers may need to adapt their sourcing strategies and production parameters or adjust their blending techniques.

"With an ever-changing climate affecting growing conditions globally, it's increasingly important to monitor the effect on existing juniper crops and be aware of new emerging growing areas," says Pauley.

The research could help gin distillers make more informed decisions about sourcing, harvest timing, and drying regimes, potentially ensuring your gin and tonic maintains its expected flavor profile despite environmental changes.

As climate change continues to affect agricultural products worldwide, for gin drinkers, their evening G&T might just become another unlikely barometer of our changing planet.

But Pauley is confident the gin industry can adapt. "Every year, the gin industry takes part in 'the big sniff,' where the current juniper harvest is evaluated, ahead of everyone buying in their supply for the next one to two years.

"So long as we are vigilant of the changes, and curiously explore different areas for harvesting the dry, piney, signature botanical of choice—your gin and tonic is in safe hands."

Matthew Pauley and Professor Annie Hill are based at Heriot-Watt's ICBD, a unique research and teaching facility that meets the needs of the brewing, distilling and malting industries worldwide.