Comparative analysis of volatile compounds of 'fino' sherry wine by rotatory and continuous liquid-liquid extraction and solid-phase microextraction in conjunction with gas chromatography-mass spectrometry

摘要

Different headspace solid-phase microextraction (HS-SPME) methods have been selected and applied to the analysis of volatile compounds in 'fino' sherry wine by gas chromatography-mass spectrometry.A method based on rotary and continuous liquid-liquid extraction (LLE) for analysis of these same compounds has been optimised.The best conditions to extract this type of compounds using SPME and LLE were determined and both methods were validated.Both methodologies show adequate detection and quantitation limits,and linear ranges for correctly analysing these compounds.The recoveries obtained were close to 100%,with good repeatability values.The analytical and procedural advantages and disadvantages of these two methods have been compared.In general,SPME presented higher sensitivities.Both analytical methods were used to analyse five samples of 'fino' sherry wine supplied by different producers.No significant differences were found between the techniques at a significance level of 5%.The regression coefficients (r~2) for analysis using LLE and SPME exceeded 0.94 for all compounds.The LLE procedure is a method with high repeatability and has the possibility of simultaneous extraction of several samples (up to 12),however the SPME technique is a solvent-free method presenting major advantages,such as small sample volume and higher sensitivity and simplicity.