Characteristics of white wines from târnave vineyard

veronica Avram, Virginia Coman and Rodica Grecu

“Raluca Ripan” Institute for Research in Chemistry,
30 Fântânele Street, P.O. Box 702, RO-400294 Cluj-Napoca,
e-mail: vavram@icrr.itim-cj.ro

Wine is a complex sample which besides water, sugar and alcohol contains a great variety of inorganic as well as organic components, so that a complete analysis - though ideal in principle - is, of course, not possible.
One of the major fields in analytical chemistry is the development of faster and easier methodologies for characterization and quantification of trace compounds in complex matrices.
Chromatographic techniques have been developed as powerful analytical methods for the separation and quantitative determination of a wide variety of compounds from complicated matrices. A feature which makes TLC (thin layer chromatography) highly attractive is that it offers the performing of simultaneous analyses. TLC permits the qualitative, semi-quantitative or quantitative examination of up to 30 samples on a single plate.
In this work some white wines from Târnave vineyard have been characterized by means of some analytical methods as TLC and UV-Vis spectrometry.
TLC was used for identification of some amino acids (proline, alanine, threonine, lysine, arginine, valine, glutamic acid, methionine, phenylalanine) and phenolics compounds (pyrogallol, pyrocatechol, resorcinol, phenol, hydroquinone) from analysed wines. The quantity and distribution of free amino acids in wine give the organoleptic profile and can be employed for the characterization of wines. The profile of amino acids defines the variety, the age and the region of wine production. The phenolic compounds influence the taste of wine and modify its colour during aging. 
The colour of white wines is given by content of flavons (yellow-brown compounds) and it has been determined by UV-Vis spectrometry.
The presented TLC and UV-Vis methods are fast and sensible and they are used for cheching of wine quality and for defining their fingerprint.

Acknowledgement: 
This work is supported by CERES National Program for the cooperation project “Researches regarding the chromatographic and electrochemical behaviour of some chemical compounds that define wine authenticity” (Contract 3-113, 2003-2005).

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