Electron spin resonance (ESR) spectroscopy study of dry-cured ham treated with electron-beam

The generation, accumulation and decay of free radicals in muscle and fat fractions from three varieties of Spanish dry-cured ham treated (0–4 kGy) in an electron accelerator have been studied by electron spin resonance (ESR) spectroscopy. In the ESR spectra from fat fractions, a well-resolved triplet signal corresponding to an alkyl radical was found only in treated samples. Linear regression models (P < 0.05) were obtained for ESR signal intensity estimation using the absorbed dose and storage time at 4 °C (from 0 to 28 days). Several ESR signals were observed in the spectra from muscle fractions related to the presence of metalloprotein complexes. However, no significant (P > 0.05) differences were found between ESR spectra from untreated (0 kGy) and treated (0–4 kGy) samples. Results suggest that the analysis of ESR spectrum in fat samples can be used to evaluate the E-beam treatment of dry-cured ham.