iTRAQ-based quantitative proteomic characterizes the salting exudates of Jinhua ham during the salting process

Exudates of ham usually generate at salting stage and it can provide complete and homogeneous biochemical information that whole ham occurred. To evaluate the effect of salting on Jinhua ham, 40 hams were randomly and equally assigned to two groups. One group was salted using 6% sodium chloride (NaCl) (LS), and the another group was salted using 8% NaCl (LS). The proteomic profile of the exudates, microstructure and curing loss of ham were investigated after salting. LS and HS groups showed a similar change in curing loss and in cell rupture from day 1 to day 7, and no obvious difference was found in the release of proteins from muscle tissue. A total of 688 proteins were identified from exudates using isobaric tag for relative and absolute quantification; sharing 70.8% of the differentially abundant proteins (340 proteins) was found in the comparison between day 1 and day 7 in both LS and HS groups. Functional annotations indicated that differentially abundant proteins primarily participated in metabolism, cell structure, binding proteins, signal transduction, and stress and defense in LS and HS groups, respectively. These results indicated that the reduction of NaCl from 8 to 6% did not cause a negative effect at salting stage of ham. Further research is needed to confirm that the effect of salting (6% NaCl) on the flavour development of Jinhua ham at ripening stage.