Determination of lactones in wines by headspace solid-phase microextraction and gas chromatography coupled with mass spectrometry.

Application of headspace solid-phase microextraction (HS-SPME) coupled with high-resolution gas chromatographic (HRGC) analysis was studied for determining lactones in wines. Six different SPME fibers were tested, and the influence of different factors such as temperature and time of desorption, ionic strength, time of extraction, content of sugar, ethanol, tannins and anthocyanins, and pH and influence of SO2 were studied. The proposed HS-SPME-GC method is an appropriate technique for the quantitative analysis of γ-butyrolactone, γ-hexalactone, trans-whiskey lactone, γ-octalactone, cis-whiskey lactone, γ-nonalactone, γ-decalactone, δ-decalactone, and γ-undecalactone in wines.

A new method for the determination of carbonyl compounds in wines by headspace solid-phase microextraction coupled to gas chromatography-ion trap mass spectrometry.

A new analytical method for the determination of 18 carbonyl compounds [2,3-pentadione, hexanal, (E)-2-hexen-1-al, octanal, acetoin, (E)-2-octenal, furfural, decanal, (E)-2-nonenal, benzaldehyde, 5-methylfurfural, (E,E)-2-cis-6-nonadienal, β-damascenone, phenylacetaldehyde, acetophenone, (E,E)-2,4-decadienal, benzophenone, and vanillin] in wines using automated headspace solid-phase microextraction (HS/SPME) coupled to gas chromatography-ion trap mass spectrometry (GC-ITMS) was developed. Five fibers with different polarities were tested, and a study of the influence of various factors such as time and extraction temperature, desorption time and temperature, pH, and ionic strength and content in tannins, anthocyans, sucrose, SO(2), and alcoholic degree was conducted. These factors were optimized using a synthetic wine doped with the different analytes.

Application of multivariate analysis and artificial neural networks for the differentiation of red wines from the Canary Islands according to the island of origin.

Eleven metals (K, Na, Ca, Mg, Fe, Cu, Zn, Mn, Sr, Li, and Rb) were determined in 83 red wines from the Canary Islands. The wines presented high concentrations of Na, and the concentrations of Cu and Zn were much lower than the maximum concentrations established by the International Office of Vine and Wine (OIV). Applying principal component analysis, the dimension space was reduced to five principal components that explain 76.