Lipidomic analysis and classification of Iberian dry-cured hams with low field NMR

Abstract

Iberian ham is a high-quality food that is traditionally produced from black pigs that are native to the Iberian Peninsula. The taste and texture of Iberian ham are largely determined by its lipid content and composition. In this work, low field 1H-NMR spectroscopy was used for the first time to analyze the lipid profile of Iberian hams as a determinant of quality. The quantification of fatty acids (FAs) is readily obtained from the integration of the spectral peaks. The FA profile is highly influenced by the diet of the pigs, with monounsaturated FAs being more prominent in hams from acorn-fed pigs. The NMR data was analyzed using a sparse partial least squares multivariate data analysis multivariate model, which allowed for the categorization of Iberian hams according to the pig's feeding regime. The main variables on which this classification is based are FA unsaturation and triacyl glyceride hydrolysis. On the other hand, there are no significant differences in the phospholipid content of the different categories of Iberian hams as determined by colorimetric and inductively coupled plasma optical emission spectroscopy methods. Benchtop 1H-NMR spectroscopy has thus revealed as an operationally simple and powerful tool for the lipid analysis and classification of Iberian hams according to the diet of pigs.