White wines from Narince grapes: impact of two different grape provenances on phenolic and volatile composition

Aim: In this study, aroma and phenolics of wines produced from Narince grapes harvested from two different localities (Emirseyit and Erbaa) of Tokat province (Turkey) were analyzed, and their effects on wine quality were assessed. Methods and results: Samples were subjected to physicochemical, total phenolics, individual phenolics and aroma compounds analyses. Gallic acid content of the Erbaa and Emirseyit wines at the end of fermentation was respectively 3.49 mg/L and 3.09 mg/L; (+)-catechin content 23.46 mg/L and 21.30 mg/L; and (-)-epicatechin content 9.46 mg/L and 8.74 mg/L. The differences in gallic acid and (-)-epicatechin contents of the wines produced from the grapes harvested from Erbaa and Emirseyit were found to be significant at the end of fermentation. A total of 31 aroma compounds were also analyzed in the wines. The aroma substances were the same in both wines (with the exception of E-3-hexanol found exclusively in Erbaa wines), but the levels were different: the wines produced from the grapes harvested from Erbaa (205605.32 mu g/L) had higher total aroma compounds than the wines produced from the grapes harvested from Emirseyit (179547.85 mu g/L). Conclusion: There were no distinctive differences in total phenolics of Narince wines produced from two different localities, but there were differences in individual phenolics and aroma compounds. Significance and impact of the study: The differences in some individual phenolics and aroma compounds of wines produced from grapes harvested from different localities are consistent with the concept of "terroir".