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Figure 4: Three batches of a US Pilsner beer - 2 canned and 1 bottled version in
comparison with (upper curve) a craft-brewed Pilsner
three different brands of the same style, namely against other barrel aged beers. Figure 4 shows data for
Bourbon whiskey. For all alcoholic beverages there three samples of the same Pilsner-style beer. Obtained
is a broad band centered around 280 nanometers. from a major US brewery two canned batches and
Though the actual peak maxima and the amplitudes 1 bottled batch show the expected consistency of
in this region differ (as seen upon close inspection product – with closely overlapping “fingerprints”. A
of the figures) between different classes and styles of craft-brewed example Pilsner is shown for comparison
beverage (1-4, 8, 9 with beer perhaps centered at closer and shows a higher amplitude fingerprint across the
to 270 nanometers, 12 and see Figures 3 and 4). The spectrum. Thus discrimination of brands of different
constituents represented under this peak region have types of alcoholic beverages are possible using UV-
been investigated closely in the case of tequila (4, 9) visible spectroscopy alone. Such fingerprinting may
and are seen to be complex Maillard reaction products also be used to study batch to batch consistency and
such as furfural although further work is needed for possibly formula changes. Furthermore, (data not
other alcoholic beverages; some specific chemical shown) we have been able to illustrate differences
constituent information is ascribed to spectral regions between forced aged vs. un-aged beverages and the
in the case for certain wines (10). Figure 2 shows the presence of spirit grade caramel when added to vodka
profiles of imported sherry examples which had seen samples. Other additives or adulterants (with unique
different regimens and or times of aging. One well aged spectral properties) might also be detected using the
example was so dark that it was off-scale over the region scanning methods outlined here (5, 8); artificial colors
of 220-350 nm and was excluded from the present data (used in some modern distilled spirits and cocktails)
set – though showed a clear distinction from the others. for example can be discriminated through spectral
Comparisons should always be made on undiluted analysis (14, 15). Most of the useful data are collected
samples whenever possible or on similarly diluted between 220 and 550 nanometers and profiles tend to
samples and with the same sample volume loaded into coalesce closer and closer to the zero baseline from
the micro-wells. For the sherry samples there are slight 550 to 1000 nanometers though the water and alcohol
shifts away from 280 nanometers as peak maxima activities are seen in the 950-1000 nanometer region
especially with the more “robust” or longer aged (16). We do note that some instruments can read
examples. Figure 3 shows the profiles for a selection of down to the 200 nanometer region and can provide
Bourbon barrel aged ales and stouts. The examples are some additional useful information pertaining to the
of more or less robustly flavored products with closely composition and profiling of beverages in the 200-220
similar profiles here on two brands (which showed nanometer region of the UV spectrum. This region is
clear organoleptic differences) and discrimination not adequately covered by the instruments we currently

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