Effect of dry-cured ham maturation time on simulated gastrointestinal digestion: Characterization of the released peptide fraction

This study deals with the identification of the peptides released after in vitro simulated gastrointestinal digestion of dry-cured Parma hams, using a physiological digestion model in terms of number of steps and composition of digestive juices. The obtained peptide mixture was analysed by ultra-high performance liquid chromatography with single quadrupole mass spectrometer detector and liquid chromatography hyphenated with triple quadrupole mass spectrometry and LTQ-orbitrap. This approach allowed for the identification of up to 81 different peptide sequences, mainly originating not only from myofibrillar proteins but also from sarcoplasmic proteins: the MW range spans between 200 and 1700 Da, with a high number of very short sequences (21 dipeptides and 12 tripeptides). Several identified released peptides are precursors of potentially bioactive sequences. The effect of the maturation time of the ham on the peptide profile obtained upon digestion was assessed: Principal Component Analysis allows for differentiating between 18 months and 24 months aged hams, underlying the importance of maturation on the digestibility of meat proteins and on the eventual release of bioactive sequences.