Stereospecific analysis of fresh and dry-cured muscle phospholipids from Iberian pigs

Abstract

A stereospecific analysis of phospholipids (PLs) from fresh and dry-cured Iberian loin was carried out in order to study the fatty acid and fatty alcohol composition of sn-1 and sn-2 positions as well as the changes in the profile of each position during the dry-cured processing. The profiles of fatty acids and alcohols in the sn-1 and sn-2 positions of PLs from fresh loin showed marked differences. Fatty alcohols were only detected in the sn-1 position. Saturated fatty acids (SFA) were located in the sn-1 position in a higher proportion ( P<0.001) than in the sn-2 one, while polyunsaturated fatty acids (PUFA) were mainly occupying the sn-2 position ( P<0.001). Dry-cured processing led to changes in the profile of each position. Thus, PUFA showed a marked decrease in the sn-2 position, monounsaturated fatty acids (MUFA) being the major family in this position in dry-cured loin PLs. Proportions of fatty alcohols in the sn-1 position increased during the processing, agreeing with the scarce or absent phospholipase (PLase) A 1 activity against the ether linkage. Moreover, no variation in the calculated amount of plasmalogens was detected between fresh and dry-cured samples, whereas there was a significant decrease ( P<0.001) in both total PLs and diacylglycerophospholipids. All these changes are most likely due to lipolytic processes rather than to lipid oxidative phenomena, although the latter could also be implied in the sn-2 PUFA decrease.