Influence of winemaking treatments and antioxidant addition on the aroma of Posip variety

Aromu vina čini više stotina kemijskih spojeva. Najznačajniji spojevi arome se sintetiziraju za vrijeme alkoholne fermentacije metabolizmom kvasaca. Ukupan udio spojeva arome iznosi od 0,8 do 1,2 g/L, a senzorski prag osjetljivosti je u rasponu od 10-4 do 10-12 g/L. Cilj ovog rada bio je utvrditi utjecaj predfermentativne maceracije, soja kvasaca te dodatka antioksidansa pri punjenju vina u boce na aromu vina Pošip. Uzorci vina su analizirani nakon 12 mjeseci odležavanja u bocama. Spojevi primarne i sekundarne arome su analizirani metodom SPME – GC/MS, dok su hlapivi tioli analizirani GC/MS tehnikom uz prethodnu selektivnu ekstrakciju tiola primjenom jakog anionskog izmjenjivača. Dobiveni rezultati pokazali su da vina proizvedena spontanom alkoholnom fermentacijom pokazuju veće koncentracije spojeva fermentacijske arome od uzoraka vina dobivenih alkoholnom fermentacijom komercijalnim kvascima. S obzirom na dodatak antioksidansa pri punjenju vina u boce, najveći utjecaj ima sumporov dioksid te kombinacija sumporovog dioksida i glutationa, odnosno u tim vinima je postignut najznačajniji antioksidativni efekt.The aroma of wine is influenced by hundreds of different compounds. The most important aroma compounds are formed during alcohol fermentation through yeasts metabolism. Wines generally contain about 0.8– 1.2 g/L aromatic compounds, and it's sensory perception threshold is ranged from 10-4 to 10-12 g/L. The aim of this study was to determine the impact of prefermentative maceration, yeast strain and the addition of antioxidants during the wine bottling on the aroma of Pošip wine. Samples of wine were analyzed after 12 months of aging in bottles. Aroma compounds were analyzed by SPME - GC/MS, while the volatile thiols were analyzed by GC/MS technique with prior selective extraction of the thiols using the strong anion exchange column. The results showed that the wines produced with spontaneous alcoholic fermentation showed higher concentrations of compounds in comparison with wine samples obtained by the alcoholic fermentation with commercial yeasts. Due to the addition of antioxidants during the bottling of wine, the highest impact had the addition of sulfur dioxide and combination of sulfur dioxide and glutathione, where the most significant antioxidant effect was achieved