The study of biochemical composition of grape and wine from Armenian selectionvariety Nrneni

Περίληψη

Background: In Armenia, autochthonous, modern cultivars, and wild grape populations are highly diverse. Different types of wine can be produced due to the climatic zones. Grapes are a popular fruit all over the world, consisting of bioactive compounds and antioxidants, such as proanthocyanidins, anthocyanins, flavonols, organic and phenolic acids, and stilbenes.  It is well known that grape varieties have different yields as well as quantitative and qualitative characteristics of the berry, which impact the quality of wine.

Objective: Conduct an in-depth study of Indigenous grape varieties and clones is essential in the development of the best wine. Our focus is to specifically study Nrneni, an artificially selected Armenian grape variety. P.K. Ayvazyan, G.P.Ayvazyan created this variety by crossing a combination of Alikante Bouchet and Cabernet Sauvignion  with Saperavi. The resulting product has pulp and juice that are an intense red color. 

Methods: In the Ararat Valley region, the grapes were hand-harvested at the end of September once they reached full technical maturity. The wine was made by the classic red winemaking method.  Physicochemical analyses of grape and wine were carried out by OIV methods. Organic acids were separated and identified using liquid chromatography.  A photocalorimetric method was used to determine the total phenolic compounds.

Results: The chemical composition of red wine made from Nrneni grapes was assessed. In the process of wine production, storage, and maturation, grapes produce a variety of other substances, including organic acids, polysaccharides, and polyphenols, some of which contribute to the wine's sensory properties (such as flavor, color, and taste) and health benefits. Grapes are excellent sources of bioactive compounds, especially polyphenols. The total and extractable anthocyanin and flavonoid content of the Nrneni grape variety was determined. The conducted studies showed that Anthocyanins were present in high amounts of 2366.4 mg/kg. Flavonoids were present in 10183.0 mg/kg in the 2022 vintage, and 3159.9 mg/kg and 12563.7 mg/kg in the 2023 vintage. Extractable anthocyanin and flavonoid amounts were 1135.87 and 4684.18 mg/kg in 2022, 1540.32 and 5836.67 mg/kg in 2023 respectively. These indicators are also high in the wine: 502.18mg/l and 2971.15mg/l in 2022 vintage, while 975.7and 4208 mg/l in 2023 vintage. Theoretical varieties are present in 8.9 g/l and 2.02 g/l in 2022, and 6.5 g/l and 1.6 g/l in 2023. Licosaccharides, acetic acids, citric acids, and succinic acids are produced by alcoholic and malolactic fermentation.

Conclusion: There is a wide range of bioactive compounds in red grapes and red wine that have been shown to have potential health benefits. According to studies, the Nrneni grape variety and the wine produced with these grapes have functional and oenological potential due to their high levels of biologically active substances, such as phenolic compounds and organic acids.

Keywords: bioactive compounds, grape, organic acids, phenolic compounds, red wine.