Influence of Cambodian traditional smoking practices on the concentration of Polycyclic Aromatic Hydrocarbons (PAHs) in smoked fish processed in Tonlé Sap area, Cambodia

Ing. Tereza Slámová

Disertační práce

Abstract:

The main aim of this work is to investigate in detail the traditional practice of smoke-cured fish from Tonlé Sap lake area, Cambodia, and to monitor the concentration of selected polycyclic aromatic hydrocarbons (PAHs) in the final product. Levels of BaP, ƩPAH4 and ƩPAH12 in 18 species of smoked fish commonly consumed in Cambodia were determined by modified QuEChERS–EMR Lipid–DLLME method and analysed by gas chromatography–mass spectrometry (GC/MS). This method was sucessfully developed and applied with a recovery rate of 50 – 120% and RSD values of <16.7%. Overall results highly exceed the limits set by the European Commission (EU) No 1881/2006. The highest ƩPAH4 and ƩPAH12 concentration were detected in Paralaubuca typus, 2701.45 μg.kg-1 and 16818.19 μg.kg-1 and the lowest measured in Paralaubuca barroni, 76.33 μg.kg-1 and 536.95 μg.kg-1, respectively. Among fish species, the highest ƩPAH4 and ƩPAH12 were detected in Paralaubuca typus (1644.19 μg.kg-1 and 9171.56 μg.kg-1, respectively). Results showed significant increase of ƩPAH12 mean values between smoking times T1 (3 – 16 hours) and T2 (1 - 4 days) and when fuel wood was used. The total fat content was measured, and the correlation between fat content and PAHs contamination was analysed, but was not proven. Altogether, the extremely high concentrations of PAHs measured in this study are attributable to a combination of factors, such as the type of fuel used and the length of the process, but other factors, such as the use of inappropriate fire-starting techniques, the use of a direct heat source, the distance from the heat source, the lack of temperature regulation systems and the size and physical state of the smoked fish cannot be excluded, although not supported by statistics in the present study. Such a burden can lead to an elevated risk of the development of diseases related to PAHs exposure. However, by following good manufacturing practices. PAHs contamination can be controlled and decreased.

Keywords

smoke-cured, food preservation, PAHs, fat content, modified QuEChERS, fish, Cambodia

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 26. 4. 2021

Obhajoba závěrečné práce

• Vedoucí: prof. Ing. Jan Banout, Ph.D.
• Oponent: Lukáš Kalous, Ph.D., prof. Ing., Bo Anne Rohlík, externi, Ondřej Urban, externi

Česká zemědělská univerzita v Praze

Fakulta tropického zemědělství

Doktorský studijní program / obor:
Zemědělská specializace / Sustainable Rural Development in TS