E. Graciani Constante

Changes in the Fatty Acid and Triacylglycerol Profiles in the Subcutaneous Fat of Iberian Ham during the Dry-Curing Process

In this study, we have evaluated the changes that occur in the profiles of total fatty acids and triacylglycerols during the dry-curing process (730 days) of Iberian ham. The subcutaneous adipose tissues of six hams obtained from three Iberian pigs fed on acorns were analyzed periodically during the processing time (from the raw to the dry-cured samples), including postsalting, drying, and ripening stages. The environmental conditions were also registered. The curing process significantly decreased (p < 0.01) the relative percentages of total polyunsaturated fatty acids, including C18:2n-6 and C18:3n-3 and, therefore, significantly increased (p < 0.05) the level of monounsaturated fatty acids. The triglycerides containing 0-2 double bonds showed an increase during the curing process. On the contrary, the more unsaturated ones (3-5 double bonds) suffered a significant decrease. We have postulated that these changes could also be due to polymerization and oxidation reactions that affect the triacylglycerols and besides the fatty acids. In general, most fatty acids and triacylglycerols reversed the trend by about 500-600 days of processing.

Application of Two heating methods in physical refining of high-FA olive and sunflower oils

Two classes of vegetable oils, olive and sunflower, were processed by physical refining in a pilot plant with a capacity of up to 30 L by means of discontinuous deodorization, and distillates were recovered by condensing and freezing using steam and nitrogen as stripping gases. Two heating systems were evaluated in the deodorizer. In the first, the deodorizer oil and the distilled gases were heated so as to maintain the same temperature in both. In the second, only the oil was heated, resulting in a difference in temperature between the oil and the distilled gases. In addition, two different oil temperatures were evaluated for each stripping gas. By means of the first heating system, the deacidification time for both oils was reduced and the efficiency of the process was notably improved. On the other hand, the higher temperature had a negative influence over both parameters. For both heating systems the sterol contents did not suffer significant variations. Substantial variations in trans FA were not observed, and the composition of FA remained stable except for linoleic acid, which decreased, although more slowly than when the temperature was not maintained, as a result of the rapid formation of its trans FA.