Speaker
Description
Wine aroma is one of the most important characteristics of wine quality and is determined by a complex mixture of volatile compounds. In this work, volatile aromatic compounds in Macedonian white wines were investigated using gas chromatography coupled with mass spectrometry (GC-MS) and two capillary columns with different stationary-phase polarities (HP5-MS with 5 % phenyl, and DB-1701 with 14 % - cyanopropyl-phenyl. Liquid-liquid extraction with dichloromethane was selected as the most suitable sample preparation procedure and was subsequently optimized to obtain optimal extraction conditions starting from 10 mL of wine and 1 mL dichloromethane and addition of 1 g of (NH4)2SO4 for pH control and 1-octanol as an internal standard.
The developed method was tested with a standard mixture of alcohols, esters, acids and terpenes and showed good sensitivity and reproducibility, with LOD values between 0.04 and 0.29 µg/mL and LOQ values of 0.41–2.93 µg/mL. Most investigated compounds showed RSD values below 10 %, indicating good analytical precision. The two columns showed complementary chromatographic characteristics. HP-5MS provided better detection of less polar compounds, particularly terpenes and long-chain ethyl esters, while DB-1701 showed improved detection and peak shape for more polar compounds, especially for carboxylic acids.
Application of the method to different Macedonian white wine varieties revealed a complex profile of alcohols, esters, terpenes, and carboxylic acids. Hexan-1-ol,
2-phenylethanol, isoamyl acetate, and several ethyl esters were consistently detected and represented important components of the wine aroma. The results demonstrate that the combined use of HP-5MS and DB-1701 enables more reliable identification and comprehensive characterization of the different classes of volatile aromatic compounds in Macedonian white wines.