In vitro anti-inflammatory and antioxidant activities and protein quality of high hydrostatic pressure treated squids (Todarodes pacificus)

This study investigated the in vitro anti-inflammatory and antioxidant properties, protein quality, and other related characteristics obtained by the single-cycle and two-cycle high hydrostatic pressure (HHP at 200, 400 and 600 MPa) treatment of squids (Todarodes pacificus). The soluble protein nitrogen content and in vitro protein digestibility increased significantly (p < 0.05) after all HHP treatments, and the two-cycle 600 MPa HHP treatments yielded the highest values, 7.59% and 84.42%, respectively. The estimated protein efficiency ratios, and antioxidant and anti-inflammatory properties of squids significantly increased by all HHP treatments. 1H nuclear magnetic resonance (NMR) showed that the main spectral changes associated to the anti-inflammatory properties of proteins following HHP treatment were in the range of 3.00-3.19 and 3.60-3.79 ppm. This indicates that the HHP treatments modified the protein and functional properties of squids and gave the relevant chemical shifts in NMR signals, either migrated or disappeared.