Dados do Trabalho

Título

GOETHE GRAPE TEXTURE PROFILE AS A GENETIC MARKER AND CORRELATION WITH WINE PHENOLIC COMPOSITION

Introdução

The grape texture profile depends on its genetic characteristics. Moreover, texture parameters perform a fundamental issue in managing the vinification process. It not only impacts the must yield, but also on phenolic extraction from grapes to wine. This study aimed to differentiate, based on texture profile, both clones of Goethe grape: Goethe Clássica and Goethe Primo, as well as investigate the correlation between the textural parameters of grapes and the wine phenolic profile.

Material e Métodos

Goethe grape clones (Clássica and Primo) cultivated in two different micro-regions from Goethe Grape’s Valley Geographical Indication were analyzed from harvests 2022 and 2023 and its respective wines were analyzed. Grape’s texture profile with the parameters of hardness (g), gumminess (g) and chewiness (g) was analyzed by a double compression test on texturometer. Wine individual phenolic profile (mg/L) was determined by liquid chromatography. Data were submitted to multivariate analysis (p<0.05).

Resultados e Discussão

Regardless harvest and micro-region, Principal Components Analysis had distinguished in the plan the Goethe Clássica samples from the Goethe Primo samples. Whereas all textural parameters analyzed were strongly correlated with Goethe clone Primo. Pearson correlation analysis demonstrated a significant correlation between all grape textural parameters analyzed and the wine phenolic content. It was observed, in 2022, a negative correlation (r>0.95) between wines’ ferulic acid content and hardness, chewiness, and gumminess in grape samples. In the same harvest, p-coumaric and protocatechuic acid showed a negative correlation with hardness (r>0.97). In the subsequent harvest, it was observed a negative correlation (r>0.98) between chewiness and vanillic and caftaric acids. Additionally, caftaric acid also showed a negative correlation with gumminess (r>0.95).

Conclusão

In conclusion, regardless of the harvest and micro-region, Goethe Primo exhibited superior texture indices. This was manifested in wines that displayed elevated levels of flavonols and hydroxybenzoic and hydroxycinnamic acids compared to Goethe Clássica. Based on the results, it was possible to observe that textural analysis is an important clonal differentiation tool and it might influence in the wine phenolic profile.