Effects of packaging methods and storage temperature on the quality of Cobia (Rachycentron canadum) fillets during frozen storage

Abstract

The aim of this study was to investigate the quality and stability of air and vacuum packaged cobia fillets (Rachycentron canadum) during frozen storage for up to 5 months at -18 oC and -25 oC. Cooking yield, water content, total volatile basic nitrogen (TVB-N), phospholipid content (PL), lipid hydrolysis (free fatty acid (FFA), and oxidation (lipid hydroperoxide values (PV) and thiobarbituric acid reactive substances (TBARS)) were measured every month of the storage period to evaluate the effects of packaging methods and storage temperature on the quality degradation of cobia fillets. Phospholipid content decreased significantly, whereas concentration of FFA increased during storage, indicating enzymatic activity throughout the storage period for all treatments. Formation of PV and TBARS increased significantly with storage time. Storage temperature and time proved to be important factors with regards to lipid degradation. Lipids were more stable at the lower storage temperature. Furthermore, the results demonstrated the inhibitory effects of vacuum packaging of cobia fillets on lipid oxidation, compared to air packaging. Interestingly, vacuum packaged cobia fillets stored at -18 oC had somewhat better quality than traditionally packaged fillets stored at a lower temperature of -25 oC.