Physicochemical, microbiological and sensory quality changes in Brama orcini fillets during 90 days of frozen storage at -25 °C

Freezing is one of the most effective methods for preserving fish quality, yet gradual deterioration can occur during storage. Extending the shelf life of underutilized bycatch species such as Brama orcini can enhance resource utilization and market potential. This study evaluated the effects of frozen storage at –25°C for 90 days on the physicochemical, microbiological, and sensory quality of skinless B. orcini fillets. Samples were assessed at 10-day intervals for drip loss (%), pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), total viable count (TVC), and sensory attributes of raw and steamed fillets. Drip loss increased slightly (p > 0.05) from 0.35% to 0.42%, while pH significantly rose from 5.27 to 6.36. TVB-N and TBARS increased significantly, reaching 25.97 mg N/100 g and 0.97 mg MDA/kg, respectively, both below spoilage thresholds. TVC remained well under the 10⁵ CFU/g safety limit. Sensory evaluation revealed gradual declines in most attributes, with juiciness showing the most pronounced reduction in both raw and steamed samples. General acceptability decreased significantly but remained within the “like slightly” range by Day 90. Overall, B. orcini fillets maintained acceptable quality for up to 90 days at –25°C. These findings support the potential of freezing as a practical strategy to extend shelf life and improve market availability of this underutilized species.