Abstract: The effects of bayberry polyphenols (BP) as a natural antioxidant and color fixative on the quality of tuna (Thunnus albacores) meat used for raw consumption during refrigerated storage were studied. Raw tuna meat was soaked in ultra-pure water (control group), 0.3 g/100 mL BP solution (BP-0.3 group), 0.7 g/100 mL BP solution (BP-0.7 group) or 0.9 g/100 mL BP solution (BP-0.9 group) for 5 min and stored at (4 ± 0.5) ℃. The freshness, color and lipid oxidation were assessed daily during storage. The results showed that BP could maintain the quality of tuna meat during refrigerated storage, significantly inhibit the increase in total volatile basic nitrogen (TVB-N) value, K value, total viable count (TVC) value, 2-thiobarbituric acid (TBA) value and metmyoglobin content (P < 0.05), and significantly retard myoglobin loss, freshness breakdown and sensory quality decrease (P < 0.05). At (4 ± 0.5) ℃, the shelf life of the control group for raw consumption was 3 days, which was extended to 5 days for the BP-0.3 group and to 6.7 days for the BP-0.7 and BP-0.9 groups. No significant difference between the BP-0.7 and BP-0.9 groups was observed as far as the preservation of tuna quality was concerned (P > 0.05). Taken together, 0.3.0.7 g/100 mL BP as a natural antioxidant and color fixative could be applied on tuna meat used for raw consumption before refrigerated storage.

Key words: tuna, raw consumption, bayberry, phenolic compounds, quality