Determination of Potential Health Hazards and Nutritional Attributes of the Fresh and Smoked Freshwater Thin-Lipped Grey Mullet (Liza Ramada)

Abstract

In an attempt to cover up the unappealing taste of the freshwater thin-lipped grey mullet (Liza ramada) and to produce a convenient agro-food product, cold smoking was applied to fish fillets followed by vacuum packaging. Based on biochemical, microbiological, and sensorial analysis, several indices were used to monitor the product quality over 60 days of refrigerated storage at 2 ±1°C. A different pattern of amine changes occurred following salting and smoking. Except for (his) and (spm); all others amines including cadaverine increased in cold smoked fillets throughout storage. The indices of atherogenicity (IA) and of thrombogenicity (IT) with values of 1.68 and 1.67 respectively, did not show a significant change during storage suggesting a stability of the fatty acids profile. However microbiological analysis limited the shelf life of thin-lipped grey mullet fillets up to 30 days of refrigerated storage. Increase of the microbial load was accompanied by a concomitant and significant (P < 0.05) rise of trimethylamine (TMA-N); volatile basic nitrogen (TVB-N) and change in sarcoplasmic and myofibrillar protein profiles in smoked fish fillet. The Ki and G values calculated from ATP-related compounds showed different pattern of change. Analysis of polycyclic aromatic hydrocarbons (PAHs) of fresh and smoked fillets showed undetectable level of benzo(a)pyrene (BaP) and the sum of PAHs (2.45 ng g −1 ) was far lower than the limit of acceptability. Data submitted to principal component analysis (PCA) showed that cold smoking process was positively correlated with results of TVB-N, TMA-N and HPX.