Determination of fatty acid content in meat and meat products: The FTIR-ATR approach.

The aim of the study was to investigate the feasibility of Fourier Transformed Infrared Spectroscopy (FTIR) on Attenuated Total Reflectance (ATR) in the determination of the fatty acid content in meat and meat products. The Multivariate calibrations were developed and proposed for Saturated Fatty Acids (SFA), Monounsatured Fatty Acids (MUFA), Polyunsatured Fatty Acids (PUFA) and Palmitic Acid. SFA and MUFA models, developed using the first derivative and the selected region 3022.33-650.15 cm-1, gave the best performance, with a coefficient of calibration r2 0.9834 and 0.9775, respectively, and the relative Root Mean Square Error of Calibration (RMSEC) 0.594 and 0.699. The best model for PUFA was obtained for region 4000.12-650.15 using the first derivative (r2 0.9817, RMSEC 0.724). Palmitic acid, chosen as the case study of single fatty acids, showed a best linear regression for the first derivative approach in region 4000.12-650.15. Results were less satisfactory in prediction in the proposed models.

Effect of IGF-II genotype and pig rearing system on the final characteristics of dry-cured Iberian hams.

The effect of the IGF-II genotype (AG vs. GG) on the morphological and compositional parameters, the fatty acid composition of intramuscular fat, the odour concentration (analysed by dynamic olfactometry) and the volatile compound profile (analysed by proton transfer reaction time-of-flight mass spectrometry) of dry-cured Iberian ham was studied for the first time, and compared to the effect of pig rearing system (high-oleic concentrated feed vs. acorn and grass). The IGF-II genotype had no effect on most variables. However, it influenced the concentration of some odorants (methanethiol and octanal), although it did not affect odour concentration. Conversely, the rearing system had a significant effect on a large number of ham variables. Results indicate a negligible effect of the IGF-II genotype on the final ham quality and confirm that the rearing system has a marked effect.

Effect of the pig rearing system on the final volatile profile of Iberian dry-cured ham as detected by PTR-ToF-MS.

The volatile compound profile of dry-cured Iberian ham lean and subcutaneous fat from pigs fattened outdoors on acorn and pasture (Montanera) or on high-oleic concentrated feed (Campo) was investigated by proton transfer reaction time-of-flight mass spectrometry. In addition to the usual proton transfer ionization the novel switchable reagent ions system was implemented which allows the use of different precursor ions (H(3)O(+), NO(+) and O(2)(+)). The analysis of the lean and subcutaneous fat volatile compounds allowed a good sample discrimination according to the diet. Differences were evident for several classes of compounds: in particular, Montanera hams showed higher concentrations of aldehydes and ketones and lower concentrations of sulfur-containing compounds compared to Campo hams. The use of NO(+) as precursor ion confirmed the results obtained with H(3)O(+) in terms of classification capability and provides additional analytical insights.