Abstract:

In this study, the free and bound flavor compounds of the fruit wines produced by Saccharomyces cerevisiae
fermentation for 90 days of Satsuma mandarin (Citrus unshiu Marc. cv. Owari) juice with and without filtration were
analyzed by solid phase microextraction combined with gas chromatography-mass spectrometry (SPME-GC-MS). Gas
chromatography-mass spectrometry olfactometry (GC-MS-O) was used to evaluate the odor properties and intensity. The
results showed that the juice filtration had a significant impact on the flavor compounds of Satsuma mandarin wine and
gave rise to significant differences in the types and contents of free and bound flavor compounds. The flavor compounds of
Satsuma mandarin wine were summarized into the following groups: hydrocarbons, alcohols, aldehydes, ketones, esters,
and acids, and the contents of free flavor compounds were higher than those of the bound ones. Esters and alcohols were the
main flavor compounds but the bound acids which act as flavor precursors were not detected in the wine. The results of GCMS-
O indicated that the two wines were significantly different in the composition of free and bound flavor compounds. A
total of 8 characteristic free flavor substances were found in the wine without pomace, accounting for 67.81% of total flavor
compounds, among which 5 compounds existed in bound form, accounting for 56.47% of total flavor compounds. A total
of 7 and 5 characteristic free and bound flavor substances were found in the wine with pomace, accounting for 48.35% and
24.21% of total flavor compounds, respectively. Thus, there are large differences in the characteristic flavor substances in
orange wines with and without pomace.

Key words: Satsuma mandsrins, fermentation, free flavor substances, bound flavor substances