Influence of Using Chitosan and Thyme during Cooling Storage of Sea Bass Fish

This study aimed to apply using some natural preservatives e.g Thyme oil and chitosan through storage and also the value of the quality parameters of sea bass through storage at 4±1°C for16 days. Fillets of fish coated with thyme oil (Thy) or chitosan (Ch) and mix of thyme oil and chitosan (Thy+ Ch) while C (control without any addition). I conducted a storage period analyses every four days. Results showed the most indicated the amino acid were glutamic addition to aspartic acid. High contents of indispensable amino acid, lysine besides leucine, were also detected. Furthermore, fatty acid profile presented that the palmitic acid (23.57%) was the primary saturated fatty acid while the major polyunsaturated fatty acids included linoleic acid, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).
This study aimed to apply and study the effect of natural preservatives thyme oil and chitosan on the storage of sea bass at 4±1°C for16 days as well as its quality parameters. Samples of the study were fillets of fish coated with thyme oil (Thy) or chitosan (Ch) and mix of thyme oil and chitosan (Thy+ Ch) while C (control without any addition). Analysis conducted every four days during storage period. Results showed the most indicated amino acid were the glutamic addition to aspartic acid. High contents of indispensable amino acid, lysine besides leucine, were also detected. Furthermore, fatty acid profile presented that the palmitic acid (23.57%) was the primary saturated fatty acid while the major polyunsaturated fatty acids included linoleic acid, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).
The chemical analyses of the results at zero time presented the pH also Total volatile base nitrogen (TVB-N) addition, Thiobarbituric acid (TBA) as well as free fatty acid were 6.48, 8.59 mg/100 g, 0 .11 mg malonaldehyde/kg and 1.23 % (expressed as % of oleic acid), respectively. The initial Psychrotrophic and Enterobactriaceae counts were 2.21 log10 cfu/g and 1.59 log10 cfu/ g, respectively. During storage, gradual increase was observed in each sample and significant variations were found among samples (P< 0.05).
The results of sensory analysis revealed that the storage period  of fish fillets was four days for control sample ,12 and 16 days in the treated with (Thy), (Ch) and (Thy+ Ch), respectively (P< 0.05). Lastly, addition of (Thy+ Ch) indicated a positive result of the storage period of fish products. However, the addition of the mixture of (Thy+ Ch) can retard unfavorable chemical changes, also lipid oxidation, increase sensory qualities and prolong the storage of the product throughout cold storage at 4°C ±1°C for16 days.