Slices of dry-cured hams (Biceps femoris muscle) were stored during 8 weeks under vacuum and modified atmospheres (100% N 2 and a mixture of 20% CO 2 and 80% N 2 ) in order to study the modifications on colour, texture and microbial counts during that period. Luminosity was found to be more stable when samples were stored with 20% CO 2 and 80% N 2 without statistical differences between vacuum and 100% N 2 . A slight whiteness was observed in the vacuum packed samples. Yellowness increased during time in vacuum packed samples, although no differences were found among the three conditions at the end of the study. Redness values were not affected by time nor by the packaging system. With regard to texture, values found for all samples were within the normal range for this type of products, although it was observed that modified atmosphere packaging preserved better samples from hardening than vacuum packaging. No safety problems were detected in relation to the microbial quality in any case. In general, no clear differences were found among the three packaging systems for colour, texture and microbial quality in the storage conditions studied.

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Simultaneous distillation extraction (SDE) and solid-phase microextraction (SPME) using a carboxen/polydimethylsiloxane fibre were compared for their effectiveness in the extraction of volatile compounds from dry-cured ham samples. A higher number of compounds was detected using SPME owing to the use of a solvent delay time in the GC-MS analysis of SDE extracts. SPME was more efficient in extracting low molecular weight and high volatility compounds, while SDE was able to extract compounds with low volatilities that were not extracted using SPME. Both techniques satisfactorily extracted most volatiles previously highlighted as odour-active compounds in dry-cured ham. However, the ratio between some compounds from lipid oxidation and those from degradation of amino acids was much lower in SDE extracts than with SPME, which could be a consequence of the development of Strecker degradation of amino acids during distillation in SDE owing to the high temperatures used. Similarly, diunsaturated aldehydes detected in SDE extracts were absent using SPME, probably owing to oxidation of polyunsaturated fatty acids in SDE as a consequence of the temperature during extraction.