Annie Hill, professor at the International Centre for Brewing and Distilling at Heriot-Watt University, is helping to lead an unusual materials experiment that sits at the intersection of chemical engineering, sustainability, and one of Scotland’s most tradition-bound industries. Working with researchers from Heriot-Watt and the team at Stirling Distillery, Hill and her colleagues are investigating whether aluminum bottles could offer a lower-carbon alternative to glass for packaging Scotch whisky, without compromising safety or quality.
Greener whisky bottles made with aluminum could replace glass (2026, January 19). Phys.org. Retrieved January 26, 2026, from https://phys.org/news/2026-01-greener-whisky-bottles-aluminum-glass.html
Glass has been the default container for whisky for generations, valued for its inertness, clarity, and association with craftsmanship. From an engineering perspective, however, it presents challenges. Glass production is energy-intensive, bottles are heavy to transport, and the environmental benefit depends strongly on collection and recycling rates. As distillers face growing pressure to reduce emissions across their supply chains, packaging has emerged as one of the remaining areas where meaningful gains might be possible.
Annie Hill, professor at the International Centre for Brewing and Distilling at Heriot-Watt University stated,
“Any innovation has to respect the craft of whiskey making while meeting the highest standards of safety. The aluminum cans we buy pulses and soup in all have liners to protect the contents from metal contamination.
The project was initiated by Kathryn Holm of Stirling Distillery, one of Scotland’s smallest producers, as the company prepares to release its first mature whisky in 2027. Having already addressed energy use and production practices, Holm approached Heriot-Watt researchers to explore whether aluminum, which is lighter and widely recycled, could serve as a viable replacement for glass in certain contexts. Similar discussions have been taking place across the drinks industry, with aluminum cans already used for beer, wine, and ready-to-drink spirits, but long-term storage of high-strength alcohol raises distinct technical questions.
At the core of the study is how whisky interacts with aluminum over time. Researchers including Dave Ellis and doctoral student Charlotte York examined spirit samples stored in aluminum containers using nuclear magnetic resonance spectroscopy and inductively coupled plasma mass spectrometry. These techniques allowed the team to track changes in organic compounds and detect trace levels of metals in the liquid.
The chemical analysis showed that certain organic acids naturally present in matured whisky, such as gallic acid formed during cask aging, can react with aluminum surfaces. In laboratory tests where whisky was stirred directly with aluminum metal, aluminum concentrations rose to levels that would exceed drinking water guidelines. While real packaging conditions are less extreme, the findings highlight a key challenge: preventing metal migration during prolonged storage.
New-make spirit, which has not yet undergone maturation and therefore lacks the same chemical profile, showed much weaker interactions with aluminum. This distinction suggests that container performance depends not only on the material itself but also on the evolving chemistry of the spirit over time. It also explains why aluminum packaging has been more readily adopted for lower-alcohol or short-shelf-life beverages.
To address safety concerns, the research examined the role of internal liners, similar to those used in food and beverage cans. Professor Hill notes that while liners are standard in aluminum packaging, the high alcohol content of whisky places additional demands on these coatings. In the tested configurations, the liner was not sufficient to fully prevent aluminum transfer during extended contact. Identifying or developing liners that can withstand high ethanol concentrations for years rather than months is now a central focus of ongoing work.
Alongside chemical testing, the team conducted controlled sensory evaluations. Under supervised conditions, tasting panels were unable to reliably distinguish whisky stored in aluminum from the same spirit stored in glass. This result suggests that, at least in the short term, any chemical changes detected at trace levels did not translate into perceptible differences in aroma or flavor. For engineers and product developers, this separation between measurable chemical interaction and sensory impact is an important consideration.
The Heriot-Watt study aligns with a broader body of research examining alternative packaging materials for alcoholic beverages. Recent studies on wine and spirits have similarly found that aluminum can be acceptable from a sensory standpoint when appropriate barriers are used, while emphasizing the need for careful materials selection and long-term testing. What distinguishes whisky is its extended storage period and high alcohol content, which amplify material compatibility issues.
For Stirling Distillery, the goal is not to displace glass entirely but to explore whether aluminum could be offered as a lower-carbon option alongside traditional packaging. Holm has emphasized that any findings will be shared with the wider industry, which must balance innovation with strict regulatory standards and consumer expectations.
From a materials science perspective, the work illustrates how sustainability challenges often hinge on detailed chemical interactions rather than simple material substitutions. Aluminum offers clear advantages in weight and recyclability, but its use in whisky packaging depends on advances in barrier coatings and a deeper understanding of spirit–material interactions over long timescales.
As the whisky industry works toward Scotland’s net-zero targets, studies like this provide a practical example of how engineering research can inform incremental but meaningful changes. Whether aluminum bottles become common on shelves remains uncertain, but the project has already helped frame packaging not as a fixed tradition, but as an engineering system open to redesign under modern constraints.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
