title: Tracing the origin of beer samples by NMR and chemometrics: Trappist beers as a case study.
abstract: An NMR and chemometric analytical approach to classify beers according to their brand identity was developed within the European TRACE project (FP6-2003-FOOD-2-A, contract number: 0060942). Rochefort 8 Trappist beers (47 samples), other Trappist beers (76 samples) and non-Trappist beers (110 samples) were analyzed by1H NMR spectroscopy. Selected NMR signals were measured and used to build classification models. Three different classification problems were identified, namely Trappist versus non-Trappist, Rochefort versus Non-Rochefort, and Rochefort 8 versus non-Rochefort 8. In all the three cases, both a discriminant and a modeling approaches were followed, using partial least squares discriminant analysis (PLS-DA) and soft independent modeling of class analogies (SIMCA), respectively, leading to very high classification accuracy as evaluated by external validation. Information regarding chemical composition was also obtained: Trappist beers contain a higher amount of formic and pyruvic acids and a lower amount of acetic acid and alanine with respect to non-Trappist ones. Rochefort beers turned out to have also a higher content of propanol and isopentanol with respect to non-Rochefort samples. Finally, Rochefort 8, shows the highest content of pyruvic acid and the lowest content of gallic, fumaric, acetic acids, adenosine, uridine, 2-phenylethanol, GABA, and alanine.
authors.affiliation: Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, Rome, Italy.|Istituto di Metodologie Chimiche, CNR, Laboratorio di Risonanza Magnetica Nucleare "Annalaura Segre,", Monterotondo, Rome, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Mannina
authors.affiliation: Dipartimento di Chimica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Marini
authors.affiliation: Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, Rome, Italy.
authors.forename: Riccarda
authors.initials: R
authors.lastname: Antiochia
authors.affiliation: Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Università di Roma, Rome, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Cesa
authors.affiliation: Dipartimento di Chimica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Magrì
authors.affiliation: Istituto di Metodologie Chimiche, CNR, Laboratorio di Risonanza Magnetica Nucleare "Annalaura Segre,", Monterotondo, Rome, Italy.
authors.forename: Donatella
authors.initials: D
authors.lastname: Capitani
authors.affiliation: Istituto di Metodologie Chimiche, CNR, Laboratorio di Risonanza Magnetica Nucleare "Annalaura Segre,", Monterotondo, Rome, Italy. anatoly.sobolev@cnr.it.
authors.forename: Anatoly P
authors.initials: AP
authors.lastname: Sobolev
mesh_terms: D001515:Beer / Q000032:analysis* / Q000145:classification*; D016002:Discriminant Analysis; D005504:Food Analysis / Q000379:methods*; D016018:Least-Squares Analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D009930:Organic Chemicals / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D009930:Organic Chemicals
keywords: Beer authentication; Nuclear magnetic resonance; Partial least squares discriminant analysis; Soft independent modeling of class analogies; Trappist beer