THE EFFECT OF GLAZING WITH SUMAC (RHUS CORIARIA, L.) EXTRACT ON THE QUALITY OF FROZEN RAINBOW TROUT (ONCORHYNCHUS MYKISS) FILLETS

EYLEM EZGI FADIOĞLU¹ , Mehmet Zülfü ÇOBAN ²

This study aims to investigate the effect of glazing with sumac (Rhus Coriaria, L.) extract on the quality of rainbow trout (Oncorhynchus mykiss) fillets during frozen storage. Fish ?llets were glazed with 5% and 10% sumac extracts and were stored at -18°C for 6 months. Results showed that glazing with sumac treatment prevented lipid oxidation when compared to non-glazed and water-glazed treatments. Sumac extract decreased the free fatty acid production during 6 months of storage. PV, TVB-N and TBA values of S5 and S10 groups were lower than NG and G groups. Samples glazed with sumac extract showed the best results compared to non-glazed and water-glazed samples. Glazing with 10% sumac extract treatment significantly decreased the total aerobic mesophilic bacteria. Our results showed that sumac can be used as natural antioxidant, antibacterial agent and glazing material for delaying lipid oxidation and to inhibit the quality loss in frozen fish.

Keywords
Sumac, Glazing, Rainbow trout, Freezing, Quality,