Abstract: This research aimed to investigate the effect of high pressure processing (HPP) (at 100–400 MPa and 20–25 ℃ for 10 min) on the hardness and water-holding capacity (WHC) of chicken breast myofibrillar protein (MP) gel with 0.3% (m/m) magnesium chloride under low salt (2.3% NaCl) condition. The underlying mechanism was explored by rheological analysis, transverse relaxation time determination and microstructure observation. The results showed that the gel hardness and WHC were significantly (P < 0.05) increased with elevated pressure levels, and the appropriate pressure was 300 MPa. HPP could promote the formation of compact, porous and cross-linking gel network structures and consequently improve gel properties of chicken breast myofibrillar protein by increasing the storage modulus (G’) and shortening the water relaxation time (T22 and T23).

Key words: high pressure processing, myofibrillar protein, magnesium chloride, gel properties