title: Classification of Coffee Beans by GC-C-IRMS, GC-MS, and (1)H-NMR.
abstract: In a previous work using (1)H-NMR we reported encouraging steps towards the construction of a robust expert system for the discrimination of coffees from Colombia versus nearby countries (Brazil and Peru), to assist the recent protected geographical indication granted to Colombian coffee in 2007. This system relies on fingerprints acquired on a 400 MHz magnet and is thus well suited for small scale random screening of samples obtained at resellers or coffee shops. However, this approach cannot easily be implemented at harbour's installations, due to the elevated operational costs of cryogenic magnets. This limitation implies shipping the samples to the NMR laboratory, making the overall approach slower and thereby more expensive and less attractive for large scale screening at harbours. In this work, we report on our attempt to obtain comparable classification results using alternative techniques that have been reported promising as an alternative to NMR: GC-MS and GC-C-IRMS. Although statistically significant information could be obtained by all three methods, the results show that the quality of the classifiers depends mainly on the number of variables included in the analysis; hence NMR provides an advantage since more molecules are detected to obtain a model with better predictions.
authors: Grupo de Investigación Ciencias, Educación y Tecnología (CETIC), Programa de Química, Facultad de Ciencias Básicas, Universidad del Atlántico, km 7 Antigua Vía Puerto Colombia, Barranquilla, Atlántico, Colombia.
authors: Victoria Andrea
authors: VA
authors: Arana
authors: Chemistry Department, Universidad del Valle, A.A. 25360, Cali, Colombia.
authors: Jessica
authors: 0000-0001-6123-3068
authors: J
authors: Medina
authors: Institut de Police Scientifique, École des Sciences Criminelles, Université de Lausanne, 1015 Lausanne, Switzerland.
authors: Pierre
authors: P
authors: Esseiva
authors: Institut de Police Scientifique, École des Sciences Criminelles, Université de Lausanne, 1015 Lausanne, Switzerland.
authors: Diego
authors: D
authors: Pazos
authors: Chemistry Department, Universidad del Valle, A.A. 25360, Cali, Colombia.
authors: Julien
authors: 0000-0002-3416-2572
authors: J
authors: Wist