Abstract: The volatile compounds in the muscle of Tilapia nilotica during 12 days of purging in autumn were extracted by solid phase micro-extraction (SPME) and analyzed by gas chromatography-mass spectroscopy (GC-MS). Totally 31 kinds of volatile compounds were isolated and identified including aldehydes, hydrocarbons, Kwai alkenes, aromatic hydrocarbons, alcohols, esters, terpenes, and others, in which aldehydes, aromatic hydrocarbons and hydrocarbons were the top three most abundant compounds, with a relative level to total volatile compounds of 36.97%, 17.85%, 20.70% at the beginning of the purging period and 44.49%, 34.65%, 8.66% at the end of the purging period, respectively. After 8 days of purging, the contents of octanal and nonanal significantly decreased, and neither octatriene nor cyclohexene were detected, which is desirable for the elimination of undesirable odor. Meanwhile, the contents of benzaldehyde and aromatic benzene ring increased, which was helpful in promoting the formation of desirable flavor in tilapia.

Key words: Tilapia nilotica, purging, volatile compound, solid phase micro-extraction, gas chromatography-mass spectrometry