Evaluation of volatile profile of Sichuan dongcai, a traditional salted vegetable, by SPME-GC-MS and E-nose

- The volatile profile of dongcai with a salting time of &, 2 or 3 was analyzed.
- 16 compounds were identified as characteristic volatile compounds in Sichuan dongcai.
- Principal component analyses based on SPME-GC-MS and E-nose discriminated the samples.
- Discrimination methods will be helpful to develop Sichuan dongcai industry.

To determine an efficient way of using its unique flavor to evaluate Sichuan dongcai, changes in volatile composition of Sichuan dongcai during fermentation with a salting time from one to three years were investigated using solid phase microextraction combined with gas chromatography-mass spectrometry and an electronic nose. In total 8, 32 and 38 compounds were detected in dongcai which were salted for 1, 2 and 3 years, respectively. The 57 detected volatile compounds and 16 common compounds were used for principal component analyses (PCA), respectively. Both groups of compounds could clearly discriminate the three samples. Both radar graph and PCA of electronic nose signals could also differentiate the three samples. However, the result of PCA by the electronic nose was more similar with that of 57 volatile compounds than the 16 common compounds. It may imply that it is better to use the total 57 compounds than the 16 common compounds when evaluating the whole flavor of dongcai. Nevertheless, either method could be helpful for ensuring the quality of Sichuan dongcai in industry.