The dynamics of biogenic amine formation in muscle tissue of carp (Cyprinus carpio)

The effect of various storage temperatures (3 ± 2°C; 24 ± 1°C and -18 ± 1°C) on the formation of biogenic amines in the muscle tissue of four hybrid lines of carp (Cyprinus carpio) with respect to microbial contamination was studied. Biogenic amines were determined by fluorescence detection HPLC based on pre-column dansylchloride derivatization. The studied microbiological parameters included total plate count, coliform bacteria count and psychrotrophic bacteria count. Concentrations of biogenic amines (putrescine, cadaverine, spermidine, spermine, tyramine, histamine and tryptamine) determined in the muscle tissue of hybrids of individual lines varied depending on temperature and storage period. All four lines showed a significant increase (P < 0.01) in putrescine, cadaverine, spermidine, spermine and tyramine concentrations over 7-day storage at 3 ± 2°C (mean values 9.7 ± 9.5, 3.4 ± 4.2, 10.1 ± 13.4, 6.3 ± 2.1 and 26.2 ± 4.7 mg/kg, respectively). No histamine was detected throughout the storage period. A health-threatening level of histamine was detected in samples stored at 24 ± 1°C for 2 days, accompanied by marked sensory changes. The highest mean value was 333.0 ± 100.0 mg/kg. Higher levels reaching significance (P < 0.01) compared with fresh fish were determined for putrescine (91.3 ± 54.6 mg/kg), cadaverine (213.0 ± 83.7 mg/kg), and tyramine (138.0 ± 45.1 mg/kg). In samples stored at -18 ± 1°C for 3 months, the content of biogenic amines did not differ at the level of significance from the values determined in the fresh muscle tissue. Putrescine and cadaverine levels were the best correlates of growing bacteria count. Significant differences between individual hybrid lines of carp were detected at none of the storage temperatures, neither between individual biogenic amines nor between the microbiological indicators determined.