Abstract of research

Improvement the Shelf Life of Tilapia Fillets Stored at Chilling Condition

Thabet M. Gerges Amany Selim and Mai Osman

Abstract

The main purpose of this investigation was to study the effect of immersing fillets of Nile Tilapia (Orechromis niloticus) in 1% acetic acid and storage under standard conditions (80% CO2: 20% N2) at a temperature of 2Â°C on their shelf life. Fillets samples were divided into four groups, Group 1 (G1): the fillets immersed in sterilized distilled water for 2 minutes and packaged in Polyamide/ Polyethylene (PA/PE) bags. Group 2 (G2): the fillets immersed in sterilized distilled water and stored under standard conditions. Group 3 (G3): the fillets immersed in 1% acetic acid for 2 minutes and packaged in PA/PE bags. Group 4 (G4): the fillets immersed in 1% acetic acid and stored under standard conditions. All samples were stored at a temperature of 2Â°C for 21 days and analyzed at the beginning of the experiment and after 7, 14 and 21 days of storage. Results of the study showed that the organoleptic properties of tilapia fillets dropped by the extension of the cold storage time to 21 days. The average values of Thiobarbituric acid-reactive substances (TBARS) in the G1, G2, G3 and G4 are 9.23, 2.56, 8.07 and 0.98 at day 21 of the cold storage at a temperature of 2 Â°C, respectively. Tilapia fillets kept under CO2-enriched atmosphere had lower total volatile base nitrogen (TVB-N) than those stored in air where the average values were 19.9, 15.93, 18.97, 15.93 mg/100g in G1, G2, G3 and G4, respectively at the end of the storage period. The results also showed that the total viable count (TVC) remained at permitted in G4 as the average number was 6.14 Â± 0.05 Ã— 103 after 21 days of storage at a temperature of 2 Â°C, while in G1, G2 and G3 were 7.53 Â± 0.06 Ã— 106, 7.63 Â± 0.11 Ã— 105 and 5.30 Â± 0.09 Ã— 10 6 respectively. Thus, the results indicated that the tilapia fillet immersion in 1% acetic acid and storage under standard conditions that have been applied in our study contributed to the extension of the validity period for tilapia fillet for a longer period of cold storage of up to 21 days.