Abstract:

Volatile compounds in samples collected at different stages during the fermentation of sufu were extracted and
analyzed by solid phase micro-extraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS). The
results showed that 110 volatile compounds were isolated and identified, which included 41 esters, 19 aldehydes, 12 ketones,
12 alcohols, 9 acids, 9 hydrocarbons and 8 other compounds. Volatile composition differed significantly across various
processing stages. More volatile compounds were detected as the fermentation proceeded. The relative contents of aldehydes
were decreased significantly after Mucor fermentation, whereas the relative contents and kinds of esters and alcohols were
increased. As the post-fermentation proceeded, the relative contents of aldehydes, acids and esters were increased gradually.
Among these volatile compounds, caproaldehyde, 2-phenylethanale, nonanal, dipentene, ethyl caproate, ethyl phenylacetate,
ethyl valerate, ethyl octanoate, 2-amylfuran and allyl methyl disulphide had an important contribution to the flavor of sufu
during the fermentation process.

Key words: sufu, solid phase micro-extraction (SPME), volatile flavor, gas chromatography-mass spectrometry (GC-MS)