Effect of storage and grilling on fatty acids in muscle of pigs fed plant oils

Abstract

The purpose of the study was to assess changes in the fatty acid composition of raw and grilled pig muscles after different storage periods. A total of 13 female and 12 castrated Pietrain x German Landrace pigs were fed a basal concentrate diet supplemented with 5% olive oil or 5% linseed oil during the growing-finishing period. An entire cut of the pork loin with bone (15 th rib to 5 th lumbar vertebra) was stored at 5 °C for 48, 96 or 144 h. Simultaneous analyses of intramuscular fat and lipid composition were carried out on raw and grilled longissimus muscles following different storage intervals. Dietary inclusion of linolenic acid by linseed oil feeding effectively increased the long-chain n-3 fatty acids, whereas in the olive oil group the oleic acid in pork was higher. Mean total lipid ranged from 1.8 to 2.3% for raw and from 2.6 to 3.5% for grilled pork chops. The relative proportions of lauric acid, stearic acid and oleic acid significantly increased with storage time, while the percentages of linoleic, arachidonic, eicosapentaenoic acid and the sum of polyunsaturated fatty acids, especially n-6 fatty acids, were decreased. Compared with raw muscle, grilling affected the relative fatty acid profile only slightly. Related to the original weight, storage and grilling increased the total fatty acid contents and the sum of saturated, monounsaturated, n-6 and n-3 fatty acids of loin chops, as a result of water losses.