Comparative effects of in-package high pressure steam sterilization and high temperature boiling on the quality changes and shelf life of ready-to-eat sea cucumber

Ready-to-eat sea cucumbers (RSC) are prone to autolysis when stored at room temperature. The objective of this study was to compare the effects of high pressure steam sterilization (HPSS) and high temperature boiling (HTB) on the biochemical, physiochemical, and structural changes of RSC stored at 25°C. After undergoing thermal treatment by HPSS and HTB, the shelf life of RSC was significantly extended to 35 and 63 days, respectively, compared to the control (CT) group. The results from TVB-N, microbial, and pH measurements indicated that both HPSS and HTB effectively maintained the quality of RSC by decreasing protein breakdown and lactic acid accumulation through glucose decomposition, thereby inhibiting microbial growth. The HPSS group showed a significant increase in soluble protein content during storage, reaching a final value of 25.48±0.36 mg/100 g on day 35, while the HTB group recorded a respective value of 12.97±0.03 mg/100 g. Furthermore, Van Gieson's staining and scanning electron microscope images revealed a tight arrangement and structural integrity of collagen fibers in the RSC of the HTB group on day 35. These findings suggested that HTB treatment was more effective in extending the shelf life of RSC and improving RSC processing compared to HPSS.