Unlike the analysis in our previous work (Li et al., 2007 and Li et al., 2009), in order to separate the EtOH and MeOH signals, generated by large concentration differences but similar retention times, the GC conditions had to be selected carefully. Fig. 1 shows a GC chromatogram of the FE HS-GC analysis of a wine sample under the selected conditions. Fig. 1a is an enlargement of Fig. 1b and shows that some minor volatile species (including MeOH) were well separated from EtOH under these conditions. Clearly, EtOH is the dominant species in the vapor phase due to its high content in the sample. Although MeOH is a minor component in wines, the GC detector (FID) is sufficiently sensitive to quantify its content using the FE HS-GC method.