A QuEChERS methodology for the determination of 3‑alkyl‑2‑methoxypyrazines in wines by gas chromatography-mass spectrometry

FONTANA A; BOTTINI R

FOOD ANALYTICAL METHODS

SPRINGER

Lugar: Berlin; Año: 2016

1936-9751

In this work, a new method for determining 3-isopropyl-2-methoxypyrazine (IPMP), 3-sec-butyl-2-methoxypyrazine (SBMP) and 3-isobutyl-2-methoxypyrazine (IBMP) in wines has been developed. QuEChERS (Quick, easy, cheap, effective, rugged and safe) and gas chromatography-mass spectrometry (GC-MS) were used as sample preparation and determination techniques, respectively. Under optimized conditions, the analytes were extracted from wine (30 mL) with 1 mL toluene in presence of 12 g anhydrous MgSO4 and 3 g NaCl. Clean-up of the toluene phase was performed by a miniaturized dispersive solid-phase extraction (d-SPE) with a combination anhydrous CaCl2 (25 mg), anhydrous MgSO4 (25 mg) and PSA (10 mg) which was effective for minimizing co-extractives and matrix effects. GC-MS parameters were also tuned-up to achieve limits of detection (LODs) between 0.0042 and 0.0071 ng mL-1 for the optimized methodology. Considering matrix-matched calibration as quantification technique, the overall recoveries (accuracy) of the method ranged between 71% and 87% for white and red wine samples, spiked at 0.04 and 0.1 ng mL-1, with relative standard deviations (RSDs) below 21%. The method was applied for the determination of target MPs in samples of commercial wines from Argentina.