Your Whisky Has Nuclear Fallout With It, And Its Used To Identify Forgeries
A major threat to the Scotch whisky industry is the sale of counterfeit single malt whiskies with purported distillation years in the 19th and early- to mid-20th centuries. However, these are often much more recent spirits, distilled in the latter part of the 20th or first part of the 21st century. These sales impinge upon the reputation of auction houses, retailers, brand owners, and distillers.
Auction sales of rare, single malt Scotch — whisky made of malted barley, produced at a single distillery in Scotland — have skyrocketed in recent years. More than 100,000 bottles were sold at auction in 2018 for a total value of $49 million. The most expensive bottle, a 1926 Macallan Valerio Adami, sold for more than $1 million.
“This massively increasing interest in the purchase of these rare products as investments has resulted in an accompanying increase in the production of fraudulent products that are difficult to detect,” the scientists wrote.
Techniques such as infrared spectroscopy and chemical analysis can separate genuine whiskeys from fakes by isolating and comparing aspects of their alcohol composition and ratios of volatile compounds. But these methods can’t confirm a whisky’s age.
The Nuclear Way
The atmospheric testing of nuclear weapons in the 1950s and early 1960s has created a precise calibration curve.
Nuclear bombs that were detonated spewed the radioactive isotope carbon-14 into the atmosphere; from there, the isotope was absorbed by plants and other living organisms and began to decay after the organisms died. Traces of this excess carbon-14 can therefore be found in barley that was harvested and distilled to make whisky and just about anything else.
Carbon-14 has a known decay rate; by calculating the amount of the isotope in a given whisky batch, scientists can then determine if a bottle’s contents were produced after the start of the nuclear age — and if that age matches the date written on the bottle’s label.
Scientists with the Radiocarbon Lab at the Scottish Universities Environmental Research Centre (SUERC) in Glasgow, Scotland, realized that accurately dating whisky based on the carbon-14 content could be tricky, as harvested barley may be stockpiled for years before being sent to a distillery. The researchers adjusted for that by creating a calibration curve, referencing carbon-14 data from whiskeys with known distillation years from 1950 to 2015.
Then, they evaluated allegedly rare whiskeys from 1847 to 1978 and found that nearly half the bottles weren’t as old as they were supposed to be. One bottle, a Talisker with a label indicating it was distilled in 1863, was likely distilled between 2007 and 2014. A bottle of Ardbeg from 1964 was probably distilled after 1995, and a Laphroaig labeled 1903 dated to 2011 or later.
In other words, despite the hefty price tags that some rare whiskeys command at auction, it would seem that sinking your money into luxury Scotch isn’t as sure as you might have hoped, according to the study.
“Our experiences have suggested that many fake products are being sold,” the researchers reported.
The findings were published online on Jan. 8 in the journal Radiocarbon.