Ukupni fenoli, stilbeni i antioksidacijski potencijal vina Babića i Plavca malog; učinkovitost pektolitičkih enzima | Total phenols, stilbene and antioxidative activity in Babić and Plavac mali wines; Eficiency of pectolytic enzymes

Croatian. Polifenoli vina posebno su važni zbog bioaktivnih spojeva i njihovog potencijalnog pozitivnog utjecaja na ljudsko zdravlje. Istraživanja prihvatljivih i sigurnih tehnologija koje će omogućiti proizvodnju vina bogatijih ovim spojevima su i potreba i izazov. Stoga je cilj ovog istraživanja bio ispitati utjecaj komercijalnih pektolitičkih enzima na ukupne fenole (UF), stilbene i antioksidacijsku aktivnost (AA) u vinima sorata Babić i Plavac mali, podrijetlom s lokaliteta osrednje kakvoće. U istraživanju su korištena dva proizvoda različitih svojstava: pektinaze s celulazama i hemicelulazama (E1) i pektinaze s inaktivnim stanicama kvasaca (E2), uz maceraciju bez dodatka enzima kao kontrolu (K). Parametri kakvoće određivani su u različitim fazama proizvodnje; od završetka maceracije i fermentacije, do vina nakon drugog pretoka i punjenja. Oba proizvoda utjecala su na parametre kakvoće. Maceracija s pripravkom pektolitičkih enzima (E1) omogućila je bolju ekstrakciju i proizvodnju vina sa značajno većom koncentracijom ukupnih fenola, obe sorte i u obe godine. Značajna pozitivna korelacija dobivena je između ukupnih fenola i antioksidacijske aktivnosti (AA). Najveće vrijednosti AA dobivene su u vinima tretmana E1, u obe godine istraživanja, kod obe sorte. Značajne razlike dobivene su kod obe sorte, ali ne u obe godine. Oba tretmana (E1 i E2) osigurala su proizvodnju vina s većim sadržajem stilbena, i pojedinačno resveratrola i piceida, međutim značajne razlike nisu dobivene u obe godine istraživanja. Zabilježene su razlike između sorata: dok je u vinima Plavca malog dominirao resveratrol, u vinima Babića je bio veći udio piceida. Unatoč relativno boljim pokazateljima kakvoće, u odnosu na kontrolu, primjena proizvoda E2 nije pokazala opravdanu učinkovitost; dobivene značajne razlike nisu potvrđene niti za jednu sortu kroz obe godine istraživanja. Tijekom dozrijevanja zabilježene su promjene ispitivanih parametara obe sorte uz smanjenje nekih pozitivnih učinaka i gubitak značajnosti u odnosu na kraj fermentacije. Zaključno, primjena komercijalnih enzima može biti poželjna u proizvodnji vina Babić i Plavac mali, s naglaskom na mlada vina.

English. Special importance of wine polyphenols have been associated with the bioactive compounds because of their benefits on human health. Research of acceptable and safe technological processes that would enable the production of wines with a higher content of such compounds is a need and a challenge. For this reason, the aim of this study was to investigate the influence of commercial pectolytic enzymes to total phenols (UF), stilbene and antioxidative activity (AA) of Babić and Plavac mali red wines, originated from middle quality localities. Two enzymatic product with different properties were used: pectinase with celulase and hemicelulase additional activity (E1) and pectinase with inactive yeast cells (E2), in comparison to maceration without egzogenous enzymes (control, K). The quality parameters were analysed in different production stages; from the end of maceration and fermentation to wine after the second decanting and bottling. Both products affected to those quality parameters. Maceration with pectolytic enzymes (E1) provided the best extraction and production of wines with the significant highest concentrations of total phenols of both varieties, in both years. The highest values of AA were obtained in wines of treatmant E1, in both years of research and for both varieties. Significant differences were obtained for both varieties, but not in both years. Maceration with egzogenous enzymes effected enrichment of wines with stilbenes, resveratrol and piceid particularly, however the significant differences did not obtained in both years of research. The differences between varieties were noted: while the resveratrol dominated in Plavac mali wines, higher proportion were obtained for piceid in Babić wines. Despite relatively better results in comparison to control, the use of product E2 was not found to be beneficial; significant differences were not confirmed for any variety during both years of the experiment. Significant positive correlation were found between the total phenols and antioksidative activity. The changes in parameters after 6 months aging were obtained in wines of both varieties, but some positive effect were reduced. The obtained differences in parameter values were not as significant as at the end of fermentation. The use of exogenous enzyme can be desirable in case of Babić and Plavac mali young wine production.