Abstract: Tuna samples were divided into four groups depending on storage temperature: 0, 4 and 15 ℃ without any pretreatment, as well as storage at 4 ℃ with ginger essential oil pretreatment. The contents of biogenic amines (putrescine, cadaverine, histamine, tyramine), trans urocanic acid and volatile basic nitrogen (TVB-N), K value, and total bacterial counts were determined at regular intervals during storage to evaluate the effects of different storage temperatures and biological antioxidant (BA) on the formation of biogenic amines in tuna and to explore the relationship between histamine and trans urocanic acid contents. The results showed that storage temperature had a great influence on the formation of biogenic amines in tuna, and the contents of biogenic amines in tuna stored at 0 ℃ were much lower than at higher temperatures. The contents of histamine, tyramine putrescine and cadaverine in samples stored at 0 ℃ for six days were 28.25, 5.47, 14.84 and 17.05 mg/kg, respectively, while after storage at 15 ℃ for six days they were 135.4, 14.63, 29.49 and 41.55 mg/kg, respectively. Histamine was the major biogenic amine in tuna, while tyramine remained at a low level throughout the storage period, and it was 16.24 mg/kg even after storage for seven days at 15 ℃. The biological antioxidant treatment could inhibit the formation of biogenic amines and microbial growth, and it could also delay protein degradation and ATP breakdown. Correlation analysis and regression analysis showed that there were high correlations of putrescine, cadaverine, histamine and tyramine with TVB-N value, K value and total viable count (TVC) with Pearson correlation coefficients of 0.804–0.981, and significant relationships between biogenic amines and TVC and TVB-N values. In contrast, there was a low correlation between trans urocanic acid and histamine with a Pearson correlation coefficient of only 0.630 for storage 4 ℃.

Key words: tuna, biogenic amines, total viable count, ginger essential oil