Lipid traits of muscles as related to genotype and fattening diet in Iberian pigs: total intramuscular lipids and triacylglycerols.

Thirty pigs were allotted into four groups according to the fattening diet ("Montanera", diet= acorns and pasture; and "Pienso", diet=concentrated diet) and genotype (Iberian and Iberian×Duroc pigs). Lipid, fatty acid and triacylglycerol compositions,were measured in Biceps femoris muscle. Fattening diet largely affected muscle lipid composition. Total intramuscular lipid and triacylglycerol contents were higher in Montanera pigs than in Pienso pigs (8.0-8.1% vs 6.0-6.8% and 7.4-7.3% vs 6.2-5.4%, respectively). In Montanera pigs, triacylglycerols contained more oleic acid (54.7-56.8% vs 53.5-53.8% and less stearic and palmitic acids (8.8-8.4% vs 9.4-10.2% and 22.2-23.3 vs 23.7-24.4% respectively) and accordingly less PSO and more POL, POO and OOO(†) triacylglycerols compared to Pienso pigs (13.1-13.6% vs 16.2-19.2%, 4.4-3.5% vs 3.0-2.7%, 53.1% vs 51.3-51.9% and 10.1-12.3% vs 8.3-8.6%, respectively). Genotype had no effect on lipid and triacylglycerol contents of muscles and showed only a slight effect on fatty acid and triacylglycerol compositions.