Determination of Volatile Compounds in Wine by Automated Solid-Phase Microextraction and Gas Chromatography

Abstract

Solid-phase microextraction in headspace mode has been applied to the determination of volatile compounds (3-methyl-1-butyl acetate, 3-methyl-1-butanol, ethyl hexanoate, pentanol, hexanol, linalool, diethyl succinate, α-terpineol, 2-phenylethyl acetate, geraniol, 2-phenylethanol and octanoic acid) in wine samples from the Denominacion de Origen Calificada Rioja using gas chromatography and a flame ionization detector. After the preliminary tests, several parameters were optimized using a Plackett-Burman design to get the most relevant variables. These parameters were: extraction time, desorption time, split ratio, magnetic stirring, type of fibre, type of injection (headspace or direct sampling) and type of salt. Five wine samples were analysed under optimum conditions. Concentrations ranging from 0.0104 mg L−1 for pentanol and 48.9 mg L−1 for 3-methyl-1-butanol were obtained. Linalool, α-terpineol and geraniol were not detected. Limit of detection ranging 0.00150-0.00800 mg L−1 and relative standard deviation ranging 1.1–5.7% were obtained.