Straightforward strategy for quantifying rotundone in wine at ng L-1 level using solid-phase extraction and gas chromatography-quadrupole mass spectrometry. Occurrence in different varieties of spicy wines

摘要

This paper presents a straightforward methodology to quantify rotundone in wine at ng L level. This compound, responsible for the black pepper aromatic note, may have sensorial relevance in some wines due to its low odor threshold, estimated at only 16 ng L in red wines. The proposed strategy is based on solid phase extraction and analysis by GC-MS. The detection limit value was 0.6 ng L, which is more than one order of magnitude below its odor threshold in wine. Matrix effects have not been found and a synthetic wine calibration was proposed. The precision of the method was evaluated in reproducibility terms, obtaining a very acceptable value (RSD 4%). The optimized and validated strategy was applied to quantify this molecule in thirty wines belonging to different varieties as Graciano, Maturana tinta, Schioppettino, Shiraz, Duras and Gamay. Two of these wines exhibited levels higher than 100 ng L.