ASSESSMENT OF THE EFFECTS OF THE SMOKE GENERATION PROCESSES AND OF SMOKING PARAMETERS ON THE ORGANOLEPTIC PERCEPTION, THE LEVELS OF THE MOST ODORANT COMPOUNDS AND PAH CONTENT OF SMOKED SALMON FILLETS

摘要

Salmon fillets were smoked by using four different smoke generation processes pyrolysis: by smouldering, with thermostatic plates or friction and liquid smoke vaporization. Different smoking times (1, 2 or 3 hours) and smokehouse temperatures (22 °Cand 32 °C) were applied. The effects of these parameters on smoked salmon flavour, odour and odorant compounds and PAH content were evaluated. Smoked salmon fillets were submitted to sensory analysis and the concentration of odorant volatile compounds were investigated by gas chromatography coupled to mass spectrometry and olfactometry (GC-MS/O/FID). Liquid smoke atomization smoking process led to products described by "cold smoke" and "vegetal" odour and flavour attributes; a PLS 2 regression shown that these odour and flavour could be related to several phenolic compounds such as syringol or p-cresol and lipid oxidation products, and pyridine derivatives, respectively. The other smoked salmons were characterized by "salmon-like" attributes for a short time and low temperature of smoking and "wood fire smoke" flavour attributes when smoking parameters increase. This organoleptique evolution could be related to the increase of the deposition of phenolic and furannic compounds with increases of smoking parameters (time of smoke exposure and smokehouse temperature). The results show a significant correlation between the smoking process parameters, and the presence of PAHs. Smouldering is the smoke generation process that leads to smoked fish with thehighest TEQs. The difference is caused by the higher levels of low molecular-weight PAHs than in fish smoked by other techniques However, the contents are always under the legal threshold concerning benzo(a)pyrene (5 mu.g.kg-1). Smoked fish obtained by liquid smoke vaporization presented the lowest level of PAHs but benzo(a)pyrene concentration is nevertheless important.