Abstract:

Rachycentron canadum fillets were stored at －10, －18 or －30 ℃ for a 90-day period of time in order to investigate the effect of different frozen storage temperatures on the physicochemical properties, textural characteristics and sensory attributes of Rachycentron canadum fillets. Temperature had a significant effect (P＜0.05) on thawing loss, cooking loss, saltextractable protein content, Ca2+-ATPase activity and TBA value during frozen storage. Thawing loss, cooking loss and TBA value increased, while salt-extractable protein content and Ca2+-ATPase activity decreased with increasing storage period and temperature. This suggests the decrease of water holding capacity, the increase of protein denaturation degree and the acceleration of lipid oxidation. The texture profile analysis (TPA) showed that the hardness and chewiness of frozen fish fillets increased significantly (P＜0.05), while the resilience decreased significantly (P＜0.05) with prolonged storage period; the hardness and chewiness decreased while the resilience value increased with decreasing temperature. The results of sensory analysis that the sensory quality of fish fillets deteriorated due to frozen storage and that higher temperatures resulted in aggravated quality deterioration. The optimal storage temperature was － 30 ℃.

Key words: Rachycentron canadum fillets, frozen storage, physico-chemical indexes, texture profile analysis (TPA), sensory evaluation