 IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 Volatile and phenolic composition of Agiorgitiko wines from eight different areas of PDO Nemea zone

Volatile and phenolic composition of Agiorgitiko wines from eight different areas of PDO Nemea zone

Abstract

AIM: Agiorgitiko (Vitis vinifera L. cv.) is the most cultivated red grapewine variety in Greece1 located mainly in Nemea region, the largest PDO zone in Greece2. Although Agiorgitiko is considered as one of the most interesting red grape varieties, not only in Greece3, but also at international level4,5, however, there is a lack of knowledge concerning the phenolic and aromatic profile of the Agiorgitiko varietal wines. For this study eight vineyards, from the most representative areas of the PDO Nemea zone, were selected in order to study the phenolic and aromatic potential of the variety and the heterogeneity of the wine composition among the different areas.

METHODS: Within the eight vineyards, vines were selected according to the same selection protocol. From the selected vineyards, 60 kg of grapes were harvested at the optimum technological maturity level using a defined picking protocol. Microvinifications were conducted, in triplicate, applying the same winemaking protocol. The produced wines were analyzed for their main oenological parameters and for their phenolic and volatile composition. Moreover, the wines were evaluated sensorially by a trained panel.

RESULTS: Phenolic and anthocyanidin content of wines ranged from medium to high levels in comparison to other international or Greek red varietal wines. Also, the volatile compounds concentrations presented differences among the wines (p<0.05) from different areas as also found when applying sensory evaluation of the samples. Statistical analysis of the sensory evaluation results illustrated an aromatic profile of Agiorgitiko wines composed by red fruit aroma descriptors and this was characterized for most of the wines analyzed.

CONCLUSIONS:

The present study provides a detailed approach on the characterization of the phenolic and aromatic content of Agiorgitiko wines, which is a great tool for improving the quality of the PDO Nemea wines. Also, in this study the variability of Nemea’s region pedoclimatic conditions that were depicted on wine and grape characteristics from different areas, implies the need of further research on the impact of “terroir” in Agiorgitiko wines produced from different areas.

DOI:

Publication date: September 1, 2021

Issue: Macrowine 2021

Type: Article

Authors

Maria Ioanna Xenia , Elli GOULIOTI, Nikolaos KONTOUDAKIS, Greece Yorgos KOTSERIDIS

AUA Department of FS&HN, Laboratory of Enology and Alcoholic Drinks, Athens, Greece,

Contact the author

Keywords

Red wine phenolics, aromatic content, agiorgitiko, nemea

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