Identification and extraction of polycyclic aromatic hydrocarbons (PAHs) from smoked fish and their Effects on the quality, microbial, and fatty acid indexes

Background and Cold-smoking is one of the most common ways to increase the shelf life of fish during storage. This study aimed to extract and measure the polycyclic aromatic hydrocarbon (PAH) carcinogens, using high-pressure liquid chromatography (HPLC)-mass, fatty acids profile, nutritional value, and bacterial community in three widely-used species of smoked fishes [Rutilus frisii (Kutum), Liza aurata, and Hypophthalmichthys molitri] of Caspian Sea, Iran. Amounts of high molecular weight (HMW)-PAHs, as indicator of carcinogenic components in smoke, showed concentrations of 0.100, 0.039 and 0.033 µg/kg in smoked Hypophthalmichthys molitrix, Liza aurata and Rutilus frisii, respectively (P < 0.05). The concentration of Benzo[a]Pyrene was calculated in Hypophthalmichthys molitrix and Rutilus frisii 0.001, and in Liza aurata 0.004 µg/kg (P < 0.05). The amounts of ω-3 in Hypophthalmichthys molitrix, Liza aurata and Rutilus frisii were 15.79%, 11.18% and 8.74%, respectively (P < 0.05). The Poleyen index amounts (EPA+DHA/C16) were 0.30% in, 0.13% and 0.14% in Hypophthalmichthys molitrix, Liza aurata and Rutilus frisii, respectively (P < 0.05). High correlation was considered between amounts of lipids and PAHs (R2 = 0.56). Number of anaerobic bacteria in smoked Hypophthalmichthys molitrix, Liza aurata and Rutilus frisii was 5.26, 5.15 and 5.18 log ufc/g, respectively and amounts of total coliform (TC) was recorded 5.21, 5.23 and 5.20 in them, respectively (P < 0.05). Contents of PAHs, quality indexes and bacterial community were at the accepted ranges and the suitable unsaturated fatty acids (UFA) and Polyen index were considerable in studied fish.