Development for a procedure for the determination of 2-phenylethanol in Hellenic wine distillates (Vitis vinifera L.) and their changes during distillation

Abstract

Aims: The aim of this work was to study the concentration, during distillation, of 2-phenylethanol, an aromatic compound, in different fractions of wine spirits and in a traditional copper alambic. Its contribution as an odorant is important due to its quality and olfactory character. This aromatic alcohol is valuable for the distilleries in order to collect the fractions with the higher participation of this compound and to specify the grape variety which gives the best results. Wine distillates or brandies are important spirits in the commercial world and are produced in many countries. The differences in the concentration of 2-phenylethanol in combination with the other congeners makes a great difference with respect to the quality of produced brandy.

Methods and results: Twenty nine red and white monovarietal wine distillates (Vitis vinifera L.) 15 red and 14 white grapes (Vitis vinifera L.), have been analysed after double distillation of monovarietal wine samples, a liquid–liquid continuous extraction with dichloromethane and an analysis by gas chromatography(FID). Pentan-3-ol was used as an internal standard. The content of 2-phenylethanol which introduces a pleasant aroma to wine distillates, resembling to rose, was determined. The concentration of this alcohol in different fractions during distillation in traditional alambic has important technological consequences.

Conclusion: The commercial fining factors in the present research affected the knowledge of the attitude of 2-phenylethanol in monovarietal spirits from selected grapes (Vitis vinifera L).This compound with this unique character of roses, plays an important organoleptioc role in commercial wine spirits, especially for the consumers which enjoy the mystagogue of brandies in order to improve the distillation technique and knowledge in wine spirits.

Significant and impact study: The knowledge of the impact of the commercial fining agent in 2-phenylethanol content during the distillation in different fractions is important for monovarietal wine spirits in order to produce qualified wine brandies. This study is also particular important for brandies production in commercial distilleries in order to separate at the right alcoholic strenght and to take fractions with the higher concentration of this alcohol which in combination of course with the minor and major other congeners gives an qualified organoleptic character.