Influence of Smoking on Indicatory PCB Congeners Residues Levels in Fish Slices
Polish Journal of Food and Nutrition Sciences
The aim of this study was do determine changes in concentrations of indicatory PCB congeners (IUPAC numbers: 28, 52, 101, 118, 153, 138, 180) during industrial hot smoking of mackerel (Scomber scombrus L.) and herring (Clupea harengus L.) slices and cold smoking of mackerel slices. PCB content in raw mackerel slices averaged from 1.32±0.29 ng/g wet w. for PCB 52 to 4.66±0.72 ng/g wet w. for PCB 153. In herring slices, PCB content ranged from 1.36±0.25 ng/g wet w. for PCB 28 to 16.50±1.94 ng/g
... o 16.50±1.94 ng/g wet w. for PCB 153. During hot smoking, losses of the examined compounds were observed -in herring slices by 15% (PCB 153) to 32% (PCB 52), while in mackerel slices by 3.7% (PCB 80) to 38% (PCB 28). Simultaneously, a slight increase in the content of PCB 180, PCB 118, PCB 153, PCB 138 and PCB 101 occurred during the proper smoking, between 1.5 th and 2.5 th hour of the smoking process. During cold smoking (26°C, 8 h), PCB concentrations increased signifi cantly (p<0.05) by 26% (PCB 28, PCB 138) to 43% (PCB 180). In the fi nal stage of smoking, PCB content in the alder sawdust and in the smoke had a signifi cant effect on the levels of the analysed PCB congeners in the smoked slices. The main parameter determining the change of these compounds contents was their decrease in co-distillation with steam. In the fi nal phase of the hot smoking a little increase of PCB compounds contents was a consequence of their penetration with smoke to the fi sh meat tissue. Original Paper Section: Food Chemistry * divided along a dorsal line FIGURE 1. A diagram of the experiment.