Free-range rearing increases (n-3) polyunsaturated fatty acids of neutral and polar lipids in swine muscles

This study was conducted to determine the effect of rearing pigs on a free-range system, on fatty acid profile of neutral and polar lipids from longissimus dorsi (LD) and masseter (MS) muscles, with special reference to n-3 polyunsaturated fatty acids (PUFA). Food sources for free-reared pigs were basically acorn and pasture, which were high in oleic and linolenic acids, respectively whereas, indoors, animals were fed a concentrate high in oleic acid. The predominantly oxidative MS muscle had lower saturated fatty acid (SFA) and higher PUFA contents than LD in neutral lipids (NL), and higher total n-3 PUFA and arachidonic acid contents and lower linoleic acid content in polar lipids (PL). Rearing the animals outdoors significantly increased total n-3 and n-6 PUFA of NL and total n-3 of PL. All n-3 fatty acids detected in PL were significantly higher in free reared animals, including eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids.