Quality assessment of sea bream (Sparus aurata L., 1758) by sensory, chemical and microbiological methods in ice, cling film and aluminium foil at 2±1°C

ABSTRACT MSc THESIS QUALITY ASSESSMENT OF SEA BREAM (Spams aurata L., 1758) BY SENSORY, CHEMICAL AND MICROBIOLOGICAL CHANGES IN ICE, CLING FILM AND ALUMINIUM FOIL AT 2±1°C Esmeray KÜLEY DEPARTMENT OF FISHERIES INSTITUTE OF NATURAL AND APPLIED SCIENCES UNIVERSITY OF ÇUKUROVA Supervisor: Asst. Prof. Dr. Fatih ÖZO?UL Year: 2004, Pages:97 Jury: Asst. Prof. Dr. Fatih ÖZO?UL Prof. Dr. Abdurrahman POLAT Asst. Prof.Dr. Işıl VAR Quality of sea bream stored in ice (22 days), wrapping by aluminium foil and cling film (15 days) at 2±1 °C was investigated by sensory (TFRU and Tony freshness scheme), chemical (TVB-N, nucleotide degradition products, nucleotide ratios and biogenic amines), and microbiological (TVC). The best quality was observed in products sored in ice during storage period. According to sensory results, the shelf life of sea bream was 18 days for ice, 8 days for aluminium foil and cling film. During storage period, TVB-N value continuously increased and reached maximum levels (65.29 mg/100 g) at end of the storage period. While the levels of ATP, ADP and AMP remain stable with low concentration (<0.4 umol/g), the contents of IMP, HxR and Hx changed significantly during storage period. For all of the storage condition, K and Ki value increased linearly with storage time. At end of the storage period, K, Ki, H and G value reached <%77, <% 82, <%55 and <%174, respectively. As biogenic amines, TMA, putrescine, cadaverine, spermidine, spermine, tryptamme, tyramine, P-phenylalanine and histamine were found mainly during storage period. TMA and putrescine were observed to increase linearly during storage period. TVC values of sea bream showed an increase with storage time and were <106 cfus/g in the corresponding organoleptic shelf life. Key Words: Sea bream, TVB-N, nucleotid degradation rate, biogenic amines, total viable count. II