title: Implementation of multivariate techniques for the selection of volatile compounds as indicators of sensory quality of raw beef.
abstract: This study was performed in order to select volatile compounds to predict the off-odour and overall assessment of raw beef's freshness Maronesa breed, using multivariate analysis. M. longissimus dorsi packed in vacuum and MAP (70 % O2/20 % CO2/10 % N2) stored at 4 ºC were examined for off-odour perception as well as the overall assessment of freshness at 10 and 21 days post mortem. The results achieved in this study demonstrated that the selected volatile compounds could be considered as volatile indicators of beef spoilage, enclosing information for discrimination of Maronesa beef samples in sensory classes of odour corresponding to unspoiled and spoiled levels. Fifty-four volatile compounds were detected. A significant increase of aldehydes, ketones and alcohols were observed during storage in MAP. 2 and 3-methylbutanal, 2 and 3-methylbutanol, 1-pentanol, 1-hexanol, 2,3-octanedione, 3,5-octanedione, octanal and nonanal were suggested as indicators of beef spoilage. 3-methylpentane was considered as a marker in the first stages of spoilage in beef, decreasing during storage. Data were examined using PCR and PLSR models for different optimal subsets of volatile compounds. The simplicity and usefulness of the technique in using 0/1 data in preserving high levels of accuracy was also prevalent. The powerful analytical methodologies for reducing variables and the choice of optimal subsets could be advantageous in both basic research and the routine quality control of chilled beef.
authors.affiliation: School of Agrarian and Veterinary Sciences, DCV, CECAV, Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Saraiva
authors.affiliation: CITAB-Centre for the Research and Technology of Agro-Environmental and Biological Sciences, Portugal School of Science and Technology, DM-University of Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal.
authors.forename: I
authors.initials: I
authors.lastname: Oliveira
authors.affiliation: School of Agrarian and Veterinary Sciences, DCV, CECAV, Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal.
authors.forename: J A
authors.initials: JA
authors.lastname: Silva
authors.affiliation: School of Agrarian and Veterinary Sciences, DCV, CECAV, Centro de Ciência Animal e Veterinária, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Martins
authors.affiliation: Tecnología de Alimentos, Facultad de Veterinaria Universidad de Extremadura, Avenida de la Universidad s/n, 10071 Cáceres, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Ventanas
authors.affiliation: Tecnología de Alimentos, Facultad de Veterinaria Universidad de Extremadura, Avenida de la Universidad s/n, 10071 Cáceres, Spain.
authors.forename: C
authors.initials: C
authors.lastname: García
keywords: Beef; MAP; Multivariate analysis; SPME-GC-MS; Volatile compounds