Multielement (H, C, N, O, S) stable isotope characteristics of lamb meat from different Italian regions

The study focuses on the 2 H/H, 13 C/ 12 C, 15 N/ 14 N, 18 O/ 16 O and 34 S/ 32 S values of defatted dry matter (DFDM) and on the 2 H/H, 13 C/ 12 C and 18 O/ 16 O values of the fat fraction of meat samples from various lamb types reared in seven Italian regions, following different feeding regimes (forage, concentrate, milk). The 13 C/ 12 C (r = 0.922), 2 H/H (r = 0.577) and 18 O/ 16 O (r = 0.449) values of fat and DFDM are significantly correlated, the fat values being significantly lower for C and H and higher for O than for DFDM values and the differences between the two fractions not being constant for different lamb types. The feeding regime significantly affected the 13 C/ 12 C, 15 N/ 14 N, 18 O/ 16 O and 2 H/H of fat. The DFDM 2 H/H, and 18 O/ 16 O values, excluding an outlier, are significantly correlated with the corresponding values in meteoric waters, thus allowing us to trace the variability of geoclimatic factors. 15 N/ 14 N is influenced by pedoclimatic conditions, whereas 34 S/ 32 S is influenced by the sea spray effect and the surface geology of the provenance area. By applying stepwise linear discriminant analysis only the 2 H/H of fat was found not to be significant and 97.7% of the samples were correctly assigned to the lamb type and more than 90% cross‐validated. With the feeding regime, 97.7% of the samples were both correctly assigned and cross‐validated using a predictive model including 13 C/ 12 C, 15 N/ 14 N, 18 O/ 16 O, 34 S/ 32 S of DFDM and 18 O/ 16 O of fat. Copyright © 2009 John Wiley & Sons, Ltd.