Integrated evaluation of freshness in coastal conger, Cynoponticus coniceps (Anguilliformes: Muraenesocidae) fillets during ice storage
DOI:
https://doi.org/10.22458/urj.v18i1.6510Keywords:
postmortem deterioration, shelf life, sensory evaluation, dielectric properties, chilled storage, fish, coastal conger, qualityAbstract
Introduction: Fish freshness is a determining factor for quality and consumer acceptability during ice storage, particularly in locally consumed species for which information on postmortem changes is limited. In this context, coastal conger (Cynoponticus coniceps) represents a poorly studied resource under commercial storage conditions. Objective: To evaluate the sensory, physical, and chemical changes associated with the freshness of coastal conger (Cynoponticus coniceps) fillets during ice storage. Methods: We described changes in freshness-related indicators of coastal conger fillets stored on ice over a 16-day period. We collected samples at eight time points during the storage period and evaluated them using sensory, chemical, and physical analyses. We conducted sensory evaluation using the Quality Index Method (QIM). We used ATP degradation and its breakdown products to calculate the K value, while we employed dielectric properties and pH as physical freshness indicators. In addition, we determined proximate composition at the beginning of the storage period. Results: Fillets had a high protein content (19,3 ± 0,58%) and moderate lipid levels. Quality Index (QI) scores and K values increased progressively with storage time, whereas torrymeter readings showed a general decreasing trend. pH exhibited temporal variation consistent with postmortem deterioration processes. Based on sensory evaluation, we identified an operational sensory rejection criterion on day 9 of storage under our experimental conditions. Conclusion: Under ice storage, coastal conger fillets suffered progressive loss of freshness, reflected by increasing QI and K values and decreasing torrymeter readings, with sensory rejection occurring on day 9. Approximate sensory shelf life is nine days under our experimental storage conditions.
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