Determination of Fatty Acids and Stable Carbon Isotopic Ratio in Subcutaneous Fat to Identify the Feeding Regime of Iberian Pigs

Abstract

Discrimination among the types of feeding regimes for Iberian pigs is currently a highly demanded challenge by the Iberian pig sector. In the present research, discrimination among feeding regimes has been achieved by the combination of two analytical methods (based on FAMEs analysis by GC-FID and determination of δ(13)C by IRMS) previously used independently without success. In the present study, 80 samples of adipose tissue from Iberian pigs subjected to four different feedings were analyzed. The study of the variables more influenced by the feeding regime has allowed us to configure panels of markers with predictive power for the studied feedings by multivariate ROC analysis. The results provided values of specificity and sensitivity higher than 85% in most cases. The statistical combination of results from different analytical methods could be the key to develop models for the correct discrimination of Iberian pigs according to the feeding regime.

Acorn Isotopic Composition: A New Promising Tool for Authenticity Maps of Montado’s High-Value Food Products

“…However, focus is on the analysis of the fatty acid isotopic composition (by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry, GC-C-IRMS) particularly comparing the 13 C/ 12 C ratio of subcutaneous adipose tissue lipids, as it is most influenced by the animals' diet. Notwithstanding, these studies [19][20][21][22][23] clearly demonstrate the possibility of distinguishing between Iberian pigs raised traditionally (only on acorns and grass during the "montanheira" period) and animals fed with other food resources (most commonly a mixture of maize, barley, and soy, possibly with added fats) based on the variabilities of δ 13 C of plant products. In this context, we hypothesize that if, we were able to discriminate acorn origin (both geographic and species) based on the isotopic signatures of acorn bulk samples (simplifying the sample preparation procedure) and streamlining results with the development of isoscapes, it would provide information regarding both Iberian pig products provenance (geographical origin) and agricultural production system status.…”

“…Several studies regarding the use of stable isotope ratio analysis to discriminate the Iberian pig feeding regime and even pig breeds are known [19][20][21][22][23]. However, focus is on the analysis of the fatty acid isotopic composition (by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry, GC-C-IRMS) particularly comparing the 13 C/ 12 C ratio of subcutaneous adipose tissue lipids, as it is most influenced by the animals' diet.…”

Selective Methods to Investigate Authenticity and Geographical Origin of Mediterranean Food Products

“…The application of stable isotope ratio analysis for authenticating Iberian pig meat products has focused on discriminating between animals fed using different dietary regimes (e.g. [28][29][30] ). González-Martín et al [31] were able to distinguish swines of different breeds (Iberian vs white) with different diets (acorns or feed) by analyzing the carbon ( 13 C) and sulfur ( 34 S) isotope composition in the liver.…”

Dietary Effects on Stable Carbon Isotope Composition of Fatty Acids in Polar and Neutral Fractions of Intramuscular Fat of Lambs

“…Thus, the analysis of δ 13 C of FA present in animal tissues using gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) has potential to discriminate the metabolic origin of FA present in animal tissues and provide new insight on the study of intramuscular fat deposition in ruminants. Recently this technique has shown potentiality in identifying the feeding regimes of pig. , …”