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Discrimination of Cognacs and other distilled drinks by mid-infrared spectropscopy
Daniel Picque1, Pascale Lieben, Georges Corrieu
1Institut National de la Recherche Agronomique, Unité Mixte de Recherche Génie et Microbiologie des Procédés Alimentaires, 78850 Thiverval Grignon, France. picque@grignon.inra.fr
Abstract:
Mid-infrared spectroscopy was applied to the analysis and discrimination of Cognacs and other distilled drinks (Armagnacs, whiskies, brandies, bourbons, rums, and counterfeit products). Strong correlations were found between dry extract spectra, polyphenolic dry extract spectra, and the total polyphenol concentration of samples, notably of Cognacs. Principal component analysis applied to spectral data made it possible to emphasize the importance of dry extract data when a distinction is made between Cognacs and Armagnacs, whiskies, bourbons, and rums, and of polyphenol concentration when Cognacs, brandies, and counterfeit products are separated. Ninety-six percent of samples in the test set were correctly assigned to Cognacs and non-Cognacs by partial least-squares discriminant analysis.
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