Grasas y Aceites, Vol 64, No 2 (2013)

A practical study on the feasibility of alpha and gamma-tocopherol quantification for distinguishing Iberian pig feeding systems

A. I. Rey
Dpto. Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Spain

D. Amazán
Dpto. Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Spain

J. García-Casco
Centro de investigación del Cerdo Ibérico, Spain


This study was undertaken to test the feasibility of using alpha and gamma-tocopherol quantification in fat and muscle to establish a correct classification of Iberian pigs according to their feeding background in practical situations. Samples were obtained over three different seasons from the four categories of pigs described in the Industry Quality Policy (FREE-OUT “bellota”; FREE-OUT-FEED “recebo”; FEEDOUT “campo”; and FEED-IN “cebo”). Linear discriminant functions were calculated with data obtained from seasons 1 and 2 and validated. The classification of fat and muscle samples from season 3 in the four feeding categories according to the calculated discriminant functions achieved an average of 76% success rate in distinguishing the true origin of pig samples. Quantification in muscle seemed to have higher prediction ability. Regression equations to quantify weight gained depending on the gamma-tocopherol concentration had higher R2 values for muscle than for fat (R2= 0.81 vs. 0.62). Merging of the feeding categories established by the Quality Policy could raise the accuracy of the alpha and gamma-tocopherol quantification method to up to between 89% and 98%.


Alpha-tocopherol; Feeding distinguishing; Gamma-tocopherol; Iberian pig

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