 IVES 9 IVES Conference Series 9 Oenological potential of indigenous greek grape varieties and their clones

Oenological potential of indigenous greek grape varieties and their clones

Abstract

AIM: Vine clone selection aims at the survival of clones with particularly desireable attributes for the production of high quality wines. The purpose of this research was to study the enological potential of the clones of Greek indigenous grape varieties over two vintages, 2018 and 2019.

METHODS: Two clones of the white grape varieties Moschofilero (E26 and E27), Assyrtiko (E11 and 16), Roditis (25E16 and 02E1E21) and two clones of the red grape varieties Xinomavro (19 and E2E30) and Agiorgitiko (03E40 and 41E47) were vinified under the same protocol for the white wines and common for the red wines in 2018 and 2019. The resulting products were studied for several enological parameters such as alcohol content, volatile acidity, pH, total phenolics, anthocyanins and tannins for the red wines, as well as browning tests for the white wines. The aroma profile of these ten samples was investigated through sensory analysis with intensity rating of individual attributes on a five-point scale by a trained panel.

RESULTS: Some common patterns of the clones’ characteristics were observed across the two vintages. In particular, wines of Assyrtiko 16 and of Roditis 02E1E21 had a lower tendency to oxidation. Agiorgitiko 03E40 was found higher in tannins compared to clone 41E47 in both years and the wine of Xinomavro 19 was richer in anthocyanins and phenolic content than clone E2E30 in both vintages, as well. Moschofilero E27 appeared more prone to oxidation than E26 in 2018, while the contrary was observed in 2019. Regarding their aroma profiles in 2018, Roditis 02E1E21 and Assyrtiko E11 were characterized by higher citrus fruit aroma intensity and Moschofilero E27 scored higher in rose aroma compared to their counterparts. Agiorgitiko 03E40 was characterized by higher cherry and blackberry intensity, while Xinomavro E2E30 was richer in olive aroma compared to their counterparts. These differences in aroma tend to appear in the wines of vintage 2019 as well, although they are not statistically significant in that vintage.

CONCLUSIONS:

This work was a first attempt to study the characteristics of two clones for each of the five main Greek grape varieties over two consecutive vintages and it denoted some significant differences in the final product of the clones. Repetition of the same study protocol in the coming vintages and careful investigation of the abovementioned quality parameters may lead to the appropriate clone evaluation and consequently to consistent products with specific varietal attributes.

DOI:

Publication date: September 24, 2021

Issue: Macrowine 2021

Type: Article

Authors

Evangelia Nanou, Sofia, NIKOLAOU, Panagiotis, TSAGGARATOS, Konstantinos, BAKASIETAS, Sofoklis, PETROPOULOS, Alexandros, KANAPITSAS, Yorgos, KOTSERIDIS

Laboratory of Enology & Alcoholic Drinks (LEAD), Agricultural University of Athens, Greece, Hellenifera & VNB Bakasietas Vine Nursery, Nemea Greece, Hellenifera & VNB Bakasietas Vine Nursery, Nemea Greece

Contact the author

Keywords

vine clone; clone selection; standard wine analysis, sensory analysis; aroma profile; greek wines

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