Insight into the Chemical Diversity of Late/Ice Harvest Gewürztraminer Wine

Abstract

Late harvest (LHW) and ice harvest (IHW) Gewürztraminer wine samples from Croatia (Ilok) were investigated. Their technological parameters, chromaticity coordinates, total phenols content, and antioxidant capacity were determined. 5-(Hydroxymethyl)furfural, xanthine, and trans-caftaric acid were analyzed in the samples by high performance liquid chromatography (HPLC-DAD). Headspace solid-phase microextraction (HS-SPME) followed by gas chromatography and mass spectrometry (GC/MS) analysis revealed isoamyl alcohol as predominant compound (21.25 - 60.30%). Diethyl succinate, 2-phenylethanol, and benzaldehyde were also abundant. Ethyl octanoate (1.48 - 5.70%) and ethyl caprate (0.48 - 4.83%) decreased significantly in LHW, being the lowest in IHW. Two solvents were applied for the samples extraction (solvent A - pentane/diethyl ether 1:2 (v/v) and solvent B - dichloromethane), and the extracts were analyzed by GC/MS. Ethyl hydrogen succinate (solvent A: 27.30 - 52.04%; solvent B: 28.04 - 46.69%) and diethyl succinate (solvent A: 5.21 - 18.2%; solvent B: 2.66 - 7.72%) were predominant in IHW and LHW. Aromatic alcohols were also found: 2-phenylethanol (solvent A: 7.07 - 21.09%; solvent B: 5.50 - 11.82%), 4-hydroxybenzyl alcohol (solvent A: 1.45 - 6.68%; solvent B: 2.47 - 12.16%) and benzyl alcohol (solvent A: 0.10 - 0.77%). The obtained results complement a previous study on IHW (Gewürztraminer) from Croatia providing new features and indicating great chemical diversity among the samples.

The Application of Headspace Solid-phase Microextraction as a Preparation Approach for Gas Chromatography with Mass Spectrometry

“…Isoamyl alcohol (3-methylbutan-1-ol; isopentanol) was the predominant (21.25-60.30 %) headspace compound in late harvest (LHW) and ice harvest (IHW) Gewϋrztraminer wine samples from Ilok, Croatia. 8 Isobutanol and isoamyl alcohol are essentially detrimental to wine quality. 9 Isoamyl alcohol is the main aliphatic alcohol synthesized by yeast during fermentation from carbohydrates and amino acids via the anabolic pathway and Ehrlich pathway.…”