Composition of characteristic aroma of Toona sinensis and its change during storage.

In order to investigate the composition of characteristic aroma of Toona sinensis (A. Juss.) Roem. and its change under different storage conditions, aroma compounds were condensed by headspace solidphase microextraction (HS-SPME). Two of 43 compounds, named A and B, which had characteristic aroma of T. sinensis, were identified by gas chromatographyolfactometry (GC-O) and GColfactometrymass spectrometer (GC-O-MS). They were shown to be sulfurcontaining by GCflame photometric detector (GC-FPD). In addition, we discussed the changes in characteristic aroma of T. sinensis with the storage time at 0 ℃, 5 ℃ and 20 ℃. The results showed that both A and B kept stable at 0℃; at 5 ℃, they did not change much in first three days, but A decreased by 44.2% while B decreased by 62.6% on the 6th day and 93.6% of A and 97.4% of B disappeared on the 12th day. At 20 ℃, both A and B decreased rapidly and there were only 3.2% of A and 1.8% of B left on the 6th day. So the higher the temperature, the more rapid decrease of characteristic aroma of T. sinensis. The optimal storage temperature should be 0 ℃.