These days, counterfeit goods are a large problem
around the world. Cheap CD items such as movies, music, or books we call
pirated and the quality may be poor reflecting the quality of the copying
process. Branded goods where we all rush
to part with cash just for the name can be a different matter in terms of
quality. The quality of the manufacture of the counterfeit can be high in many
cases.
If it’s a watch and it doesn’t tell the time
accurately or isn’t waterproof, then we can see it’s a poor quality
counterfeit. If the quality is high, how do we know then? Many items can have
markers such as unique serial numbers on them, but that doesn’t work for what
we eat or drink.
Single malt Scotch is a popular tipple around the
world and some brands with long sojourns in the cask are sought after and
demand prices outside the capabilities of my wallet. These are prime targets
for counterfeiters, but how would we of the uncultured palate know?
Ashok et al from
the U of St. Andrew’s have come to our aid and have designed a Scotch Fake
Detector on a tiny microfluidic chip that only steals a drop of Scotch from
your closely guarded glass (1). This
portable device connects up to a Raman Spectrometer. So won’t fit into our
messenger bag with our iPad and our wallet recovering in darkened seclusion
from the shock of paying for the glass of hooch that your suspicious about.
As the Raman pattern is due to the inelastically
scattered light from the vibrational states of the molecules in the whisky, the
complex molecular blend that gives your chosen tipple its characteristic nose
and flavor will give a unique Raman pattern, like your fingerprints.
The problem is there are strong peaks from the
ethanol that is in the whisky and that can vary slightly for different brands,
but that isn’t enough. More exciting though is the analysis of the fluorescence
background. The age of a Glenfiddich could be clearly estimated and a 12-year
old separated from a 15-year old with an 18-year old being very different
again.
The Glenmorangie distillery enjoys using different
wine casks for ageing and again the background indicated very clearly if
sherry, port, sauternes or simple old oak casks had been used.
For this to be a good anti-counterfeiting method a
very large central library of spectra would have to be built up. Collecting
samples from all over would leave the lab with a surplus sample disposal
problem that I may be able to help with.
- P.C. Ashok, B. B. Praveen & K. DHolakia, Optic Express, 19, 22982, (2011).
