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The effects of dietary fat composition and vitamin E supplementation on the quality characteristics of dry-cured Iberian hams ripened for two years were studied. Thirty Iberian Duroc pigs were fed diets containing three levels of poly and monounsaturated fatty acids. Within each dietary fat treatment, one group was fed a basal level of vitamin E (20mg α-tocopheryl acetate/kg diet) and the other group received a supplemented level (200mg α-tocopheryl acetate/kg diet). Dietary fat composition significantly affected total saturated fatty acids content of neutral and polar lipids from dry-cured Iberian ham ( p 0.012 and p 0.003, respectively). However, diet fatty acids composition did not influence either total monounsaturated or total polyunsaturated fatty acids of neutral and polar lipids. Vitamin E supplementation significantly enhanced dry-cured Iberian ham α-tocopherol content ( p 0.001). This, in turn, led to significantly lower levels of TBARS on days 6 and 9 of storage in slices from dry-cured Iberian hams made of vitamin E supplemented pigs and also lower oxidation levels in an induced lipid oxidation test in samples from those pigs. Dietary fatty acid composition did not significantly affect either TBARS during slices storage or malonaldehyde content in the induced oxidation test. No effect of vitamin E supplementation was observed in ham volatile aldehyde profile, but dietary fat significantly affected hexanal ( p 0.02), heptanal ( p 0.05) and total aldehyde content ( p 0.02), with those pigs fed a diet rich in PUFA showing higher values. Using diets supplemented in α-tocopherol and rich in monounsaturated fatty acids seemed adequate dietary strategies for feeding Iberian hams reared indoors.

The effects of some biotic (pig-rearing system and muscle location) and abiotic factors (processing time and drying location) on colour ( L*, a* and b*) and moisture changes during the manufacture of Iberian ham were studied. The levels of L* (from 27.14 to 44.44), a* (from 6.10 to 19.84) and b* (from 2.18 to 8.72) parameters, and moisture (from 31.71 to 75.04) decreased ( p 0.05) as processing time increased. L*, a* and b* were strongly influenced by muscle location and their values were smaller ( p 0.05) in semimembranosus than in biceps femoris, as occurred with moisture. The rearing system produced differences ( p 0.05) in a* at the first stage and in L* and b* at the final stage of processing. Drying location, probably in association with natural climatic conditions, caused differences ( p 0.05) at only the final stage of processing in a* and b* parameters. The variations in colour parameters were mainly affected by rearing system and muscle location.

Several volatile compounds from Iberian ham trapped from the headspace were analysed to research the effect of crossbreeding (Iberian vs. Iberian Duroc 50% pigs) and rearing system (Montanera system vs. Pienso system) on them. Thirty-four Iberian hams grouped following a factorial treatment structure were analysed. A two-way analysis of variance with interaction was applied to the data from 46 volatile compounds identified. The effect of crossbreeding was negligible on the studied volatile compounds, which was in agreement with the effect on fatty acid percentages of subcutaneous fat. On the contrary, the effect of rearing system was significant in most of the fatty acid percentages used to classify the hams into the current commercial grades of Iberian ham (16:0, 18:0 and 18:1, p

The effect of feeding regime—free—range reared on acorn and pasture, or in confinement with and without the incorporation of 100 mg/kg α-tocopheryl acetate to pig mixed feeds—on volatile alde hyde content in Biceps femoris muscle throughout the ripening of Iberian ham was studied. Saturated aldehydes from 4 to 10 carbon chain and two diunsaturated aldehydes, 2,4-nonadienal and 2,4- decadienal, were found in ham samples. Volatile aldehyde evolution was not affected by feeding regime throughout ripening of hams. Volatile aldehyde content and individual aldehydes rose mark edly from Day 0 to Day 210 ( p < 0.05), and afterwards decreased to Day 700 ( p < 0.05). Both α- tocopheryl acetate supplementation and feeding on acorn and pasture significantly decreased the total and individual aldehydes in Biceps femoris samples at Days 0, 210 and 700 ( p < 0.05) in compari son with muscle samples from pigs fed the non-supplemented diet.

Non-protein nitrogen and its fractions (peptides, amino acids and volatile basic nitrogen) were determined in biceps femoris and semimembranosus muscles of two homogeneous groups of Iberian dry-cured ham in different stages of maturation, and ripened in two different factories under different environmental conditions. A progressive increase in non-protein nitrogen was observed during ripening in all groups, being especially intense during the drying stage, when the temperature was the highest during maturation. During the first stages of processing, the proportion of peptides and free amino acids remained similar while free amino acids increased more markedly from the drying stage, representing the largest fraction at the end of the process. Volatile basic nitrogen was the least abundant fraction of non-protein nitrogen during ripening. Hams kept at higher temperature during longer periods, and with lower salt content, produced larger amounts of all three fractions of non-protein nitrogen in fully ripened dry-cured Iberian ham.