Slashdot Mirror
Nuclear Testing Helps Identify Fake Vintage Whiskey
Hugh Pickens writes "Industry experts claim the market for vintage whiskey has been flooded with fakes that purport to be several hundred years old but instead contain worthless spirit made just a few years ago. Now researchers at the Oxford Radiocarbon Accelerator Unit have developed a method that can pinpoint the date a whiskey was made by detecting traces of radioactive particles created by nuclear bomb tests in the 1950s. '"It is easy to tell if whiskey is fake as if it has been produced since the middle of the twentieth century, it has a very distinctive signature," says Dr. Tom Higham, deputy director of the facility. Nuclear bomb testing in the 1950s saw levels of carbon-14 in the atmosphere rise around the world so the amount of isotope absorbed by living organisms since this time has been artificially elevated. Whiskey extracted from antique bottles is sent to the laboratory where scientists burn the liquid and bombard the resulting gas with electrically charged particles so they can measure the carbon-14 in the sample. In one recent case, a bottle of 1856 Macallan Rare Reserve was withdrawn from auction at Christies, where it was expected to sell for up to £20,000, after the scientists found it had actually been produced in 1950. "So far there have probably been more fakes among the samples we've tested than real examples of old whiskey," says Higham.'"
1. The older a whiskey is the more expensive it gets due to rarity, not quality. Many people have a bias toward older whiskeys (whiskies) because they think they are better. Like wine, some whiskeys age well, others don't.
2. Whiskey must be stored in oak barrels to age. Once it is out of the barrel, and in a bottle or steel vat, it no longer ages. So a 10 year old whiskey sitting in a bottle for 50 years is still a 10 year old whiskey.
3. Whiskeys in barrels lose about 2% a year due to evaporation, known as the angel's share. That 2% is mostly water in hotter climates, but in cooler ones, like Scotland, what is lost is mostly alcohol. Thus a spirit which is put into a barrel at 60% alcohol by volume (ABV) will be reduced to 50% ABV then 40% ABV as time goes one. This is important because once the produce drops below 40% ABV, it can no longer legally be named whiskey. Thus whiskeys are usually never older than 40 years of age to due the angle's share.
4. Whiskey is how it's spelled in the USA (where I am writing this.) In Britain and Canada it is spelled whisky. Since the article discusses whisky from The Macallan distillery (yes the "T" is capitalized), the article's title and summary misspelled "whisky."
Atmospheric contaminants are routinely used to date the age of groundwater (e.g., in wells) and even to measure the residence time for water in the watershed of rivers. The most commonly used radioactive element is the hydrogen isotope, tritium. You can see a curve for it here, where the tritium level peaks in 1964 or so. You measure how much tritium is in the groundwater, then you compare it to that curve to which I linked after accounting for the decay of the tritium (half-life = 12.32 years), the match shows when that water fell as rainfall. Lot's of different contaminants are that way: CFC's used in air conditioners were useful until they were banned, SF6 is used in industrial transformers and does the same job.
Gentlemen! You can't fight in here, this is the war room!
Whiskey (or any liquor that is aged for flavor) only ages "in the barrel". Once it is bottled, it does not age anymore, because glass is inert. So if your grandfather bought a bottle of 12 year old Chivas in 1960 and left it gathering dust in his liquor cabinet for the next 49 years, you do not have 61-year old scotch, you have 12 year old scotch that's been in the bottle for 49 years. The value in these old bottles is not necessarily in their age per se, it's in their rarity - many of these old distilleries have long since ceased production and gone out of business, their recipes are lost, and the old bottles represent a legacy of sorts for the regional producers who thrived before giant corporations took over the production of spirits. It's kind of like buying NOS (new old stock) stickers for your MAME cabinet or arcade build. Only in this case, the "relics", such as they are, are a link to the past that simply can't be recreated once they're gone. The process that's descibed in the article ensure that the unscrupulous among us don't try to take advantage of people's desire to connect with that which came before.
Blogging Weight Loss, Distance Education, and more at verlin.com
We can compare C-14 dating to other known dates. For example, C-14 dating agrees with dating from dendrochronology(the fancy word for counting tree rings). C-14 dating also agrees with other forms of radioactive dating and known historical data. We can be very sure there hasn't been any spike in the last 9000 years or so. Sudden spikes would also show and make a lot of archaeology just not look like it made any sense. And if there were any form of spike we'd likely see an impact in the ratios of other isotopes. If there had been substantial nuclear detonations for example, we'd be able to tell.
A spike won't add a uniform extension or contraction to dates. For most forms of spiking, you'll get a lot of stuff looking like it is from a very short time period or you'll get a very large period where you don't see almost anything (depending on whether you have a process adding too much C-14 or reducing C-14 levels). We can be pretty sure that C-14 dating is accurate.