Abstract:
To investigate the influence of frozen durations on the water adsorption characteristics of pre-cooked sea cucumber (PCSC), the samples were frozen at −20 ℃ for 0, 1, 3, 6, 12 months, respectively. Changes in physical properties (sensory quality, water absorption ratio, water holding capability, moisture content, texture properties, and microstructure), chemical composition (water-soluble collagen content, TCA-soluble oligopeptide content, glycosaminoglycan concentration), and Fourier transform infrared spectroscopy were comprehensively monitored and analyzed. The results demonstrated that the sensory properties of frozen PCSC gradually deteriorated with the extension of the storage period. Specifically, the water absorption ratio of the samples frozen for 12 months decreased by 18.61% compared with that o duration f non-frozen samples (P<0.05), while the water holding capacity significa resilience
of ntly decreased by 19.21% (
P<0.05). However, no significant effect was observed on the moisture content due to extended frozen durations. Additionally, hardness, cohesiveness, springiness, chewiness, and resilience of deteriorated with prolonged storage frozen PCSC declined as the storage time increased. After three months of frozen storage, there were no obvious differences in appearance. However, collagen fibers showed remarkable dissolution. Storage beyond six months of frozen storage led to a notable deterioration in apparent quality as well as the deformation of collagen fiber structures into a foam-like consistency. Significantly increased levels of water-soluble collagen, TCA-soluble oligopeptides, and glycosaminoglycans were observed during frozen storage (P<0.05), further confirming that both collagen degradation and structural integrity within the sea cucumber body wall deteriorated over time with extended preservation periods. The research findings provide both theoretical insights and scientific bases for considerations regarding the shelf-life and subsequent intensive processing protocols for frozen PCSC.