2. Experimental
.1. Reagents
Water used in this study was prepared in our
laboratory using a Millipore (San Jose, CA, USA)
Milli-Q Gradient system at an output of 18.2 MV.
Four alcohols (methanol, ethanol, 1-propanol and
1-butanol) were purchased from Wako Pure Chemical
(Osaka, Japan). For chromatographic analysis,
these alcohols, as well as commercially available
alcoholic beverages, were dissolved in water so as
the concentration of alcohols might be 1–2% (v/v).
2 .2. HPLC–FID
A schematic diagram of the HPLC–FID system
employed in this study is presented in Fig. 1. The HPLC–FID system consisted of a Shodex (