Abstract:

Pre-rigor Rex rabbit meat was subjected to high pressure processing at 100, 200 and 400 MPa, respectively,
at 25 ℃ for 15 min prior to storage at －18 ℃ for 24 h. The quality and ultrastructure of the rabbit meat were studied.
With increasing pressure, L* increased, a* decreased and the reddish meat turned gray. Furthermore, cooking loss rate
and drop loss rate showed an upward trend after the first drop. The lowest drip loss and cooking loss (31.54% and 2.61%,
respectively) were observed for rabbit meat when treated with 200 MPa. Ultra high pressure (UHP) had a significant effect
on the tenderness of rabbit meat (P ＜ 0.05). The shear force declined as the pressure increased from 0.1 to 200 MPa, but
sharply increased at 400 MPa to be significantly higher than that of the control group (0.1 MPa). There were only little
changes in the organizational structure of the meat treaded with 100 MPa as compared to that of the control group (0.1 MPa).
However, UHP processing at 400 MPa significantly altered the microstructure of rabbit meat: sarcomere contraction, muscle
fiber distortion and fragmentation, protein depolymerization and tertiary structure were all destroyed. These results showed
that ultra -high pressure causes significant effects on the quality and ultrastructure of pre-rigor Rex rabbit meat and that the
best ultra-high pressure condition for pre-rigor rabbit meat is 200 MPa.

Key words: ultra high pressure (UHP), pre-rigor, rabbit meat, quality, ultrastructure