The effect of meat quality, salt and ageing time on biochemical parameters of dry-cured Longissimus dorsi muscle.

Pieces of Longissimus muscle were used as models of dry-cured ham to study the effect of NaCl concentration, meat quality and ageing time on the biochemical parameters related to the ham curing process. Higher amounts of added salt did not result in an increase in the protein extractibility. The activity of the lysosomal enzymes cathepsins D and B showed dependence on the ageing time, whereas cathepsin B and cathepsin B+L activities depended on meat quality. Cathepsin B+L activity increased with the addition of salt. Meat quality had an influence on all the parameters studied except on MFI, on cathepsin D activity and on the inhibitory activity on cathepsin B. Two protein bands likely to correspond to titin and nebulin were detected in the pherograms of myofibrillar proteins of muscle even those aged for as much as 48 h and irrespective of meat quality. Titin was also found in the sarcoplasmic protein fraction of salted samples from N and DFD meat, but not from PSE meat.