One of Scotland’s smallest distilleries is working with Heriot-Watt university to see if aluminium could replace glass bottles for its Scotch whisky.
Stirling Distillery wanted to investigate how whisky behaves when stored in aluminium as opposed to traditional glass bottles.
Kathryn Holm, Head of Communications and Marketing at Stirling Distillery, said: “Glass has long been central to whisky’s image; it’s weighty and evokes the craftsmanship of the spirit.
“But it is also heavy to transport and relies on high recycling rates to reduce its environmental impact.
“Aluminium is lighter and widely recycled, so I asked the experts to investigate whether it is a viable alternative.”
Researchers from Heriot-Watt combined advanced chemistry with sensory tests to assess whether aluminium interacts chemically with whisky in a way that alters its flavour or, most importantly, raises safety concerns.
Spirits supplied by Stirling Distillery were placed in aluminium bottles and tested over several months.
Dr Dave Ellis, Assistant Professor at Heriot-Watt, said: “We know that certain organic acids naturally present in matured whisky can react with aluminium, which can lead to aluminium entering the liquid.
“If we stir samples with aluminium metal, the levels were well above what would be considered acceptable for drinking water.”
The chemistry showed that compounds such as gallic acid, which develop during whisky maturation, were reduced or removed after prolonged contact with aluminium.
These reactions were much less pronounced in new make spirit, which has not yet developed the same chemical profile.
Dr Annie Hill, Professor at Heriot-Watt, said the traditional protective liners used in food cans were currently insufficient for aged spirits.
She said: “The next stage of this research would be to find a liner that can withstand high alcohol levels for a prolonged period of time without degrading.”
However, she continued that panellists could not distinguish between whisky stored in aluminium from whisky stored in glass.
Therefore, the changes detected in the laboratory did not translate into differences in aroma.
Ms Holm said the research would be shared with the wider industry, which is under pressure to meet Scotland’s net zero targets while maintaining regulatory standards.
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