Feasibility study on the use of infrared spectroscopy for the direct authentication of Iberian pig fattening diet

• Published in: Analytica chimica acta Vol. 636; no. 2; pp. 183 - 189
• Main Authors: Arce, Lourdes, Domínguez-Vidal, Ana, Rodríguez-Estévez, Vicente, López-Vidal, Silvia, Ayora-Cañada, María José, Valcárcel, Miguel
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 23.03.2009; Elsevier
• Subjects: Analytical chemistry; Animal Feed; Animals; Chemistry; Classification; Discriminant Analysis; Exact sciences and technology; Fat analysis; Feasibility Studies; Fourier transform infrared; Iberian pig; Linear discriminant analysis; Near infrared; Oleic Acid - chemistry; Spectrometric and optical methods; Spectroscopy, Fourier Transform Infrared - methods; Spectroscopy, Near-Infrared - methods; Subcutaneous Fat - chemistry; Swine; Iberian pig; Fat analysis; Linear discriminant analysis; Fourier transform infrared; Near infrared; Classification; Discriminant analysis; Fourier transform spectroscopy; Feasibility studies; Fatty acids; Fattening; Discriminant function; Pig; Infrared spectrometry; Near infrared spectrometry; Vertebrata; Mammalia; Oleic acid; Fat; Feasibility; Artiodactyla; Ungulata; Principal component analysis
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2009.01.058

The feasibility of using both middle- and near-infrared spectroscopy for discrimination between subcutaneous fat of Iberian pigs reared on different fattening diets has been evaluated. The sample set was formed by subcutaneous fat of pigs fattened outdoors (extensively) with natural resources ( montanera) and pigs fattened on commercial feeds, either with standard feed or with especial formulations with higher content in oleic acid (HO-formulated feed). Linear discriminant analysis was used to classify the samples according to the fattening diet using the scores obtained from principal component analysis of near- and middle-infrared spectra as variables to construct the discriminant functions. The most influential variables were identified using a stepwise procedure. The discriminant potential of each spectral region was investigated. Best results were obtained with the combination of both regions with 91.7% of the standard feed and 100% of montanera and HO-formulated feed samples correctly classified. Chemical explanations are provided based on the correlation of these variables with fatty acid content in the samples.