Abstract.
A new methodology was developed for determination of caramel in spirits aged in oak casks. The method is based on differences
between the electronic spectra of oak aqueous alcoholic extracts and caramel solutions in the same solvent. The data were treated
by 2 different approaches: the simplest one was based on the plot of caramel concentration versus the ratio of absorbance at 210
and 282 nm; the other was based on a partial least squares (PLS) calibration model using the first derivative of the spectral data.
Both methodologies were applied to analysis of 159 aged spirit samples. The mean caramel content of several Brazilian sugar cane
spirits (cachaça) and all United States whiskies was smaller than that of Scottish whiskies and other brandies from several countries.
Correlation was good between caramel concentrations for the same sample calculated by the 2 methods. The uncertainties following
PLS and the absorbance ratio method were 0.01 and 0.03 g/L, respectively, for a sample containing 0.45 g/L caramel. Treatment
of UV-VIS spectra by pattern recognition using hierarchical clustering analysis and principal components analysis allowed
discrimination of the samples as a function of their caramel content. It was possible to distinguish U.S. whiskies from other whiskies,
but a clear differentiation among Brazilian cachagas as a function of their geographic origin was not feasible. Small caramel quantities
as low as 0.08 g/L were clearly detected by these methodologies.

Keywords.
 

Keywords Plus.
Maturation; Beverages; Brandies; Whiskey.