Influence of muscle type on the evolution of free amino acids and sarcoplasmic and myofibrillar proteins through the manufacturing process of Celta dry-cured ham

•Moisture content was higher in biceps femoris than in semimembranosus muscle.•Proteolysis was significantly higher in biceps femoris than in semimembranosus muscle.•Free amino acid content reached higher values in BF than in SM muscle.•The two muscles also differed in the free amino acid profile.•Myofibrillar proteins were more intensely degraded in BF than in SM muscle.

The effect of the muscle type [semimembranosus (SM) and biceps femoris (BF)] on the evolution of free amino acids and sarcoplasmic and myofibrillar proteins throughout the manufacture of Celta dry-cured ham was studied. A total of thirty Celta hams were analyzed, 5 in the green stage, 5 after the end of the salting stage, 5 after 120 days of post-salting, 5 after the end of the drying-ripening stage, 5 after 165 days and 5 after 330 days of “bodega” step. Possibly due to its higher moisture values, the BF muscle underwent higher protein degradation than the SM muscle. The average of total FAA content increased significantly (P < 0.001) from 567.3 and 570.3 mg/100 g of dry matter in the raw pieces to 7884.1 and 4595.9 mg/100 g of dry matter at the end of the “bodega” stage for BF and SM muscles, respectively. SDS-PAGE analysis also revealed that myofibrillar proteins were more intensely degraded in BF muscle, differences being more evident for the 48.9 kDa and 33.1 kDa proteins.