Characterization of bioactive compounds from grape juice and pomace by using mass spectrometry methods and examination of juice enrichment potential

Polifenoli dokazano imaju vrlo jako antioksidativno, kardioprotektivno, neuroprotektivno i antikancerogeno djelovanje zbog čega je uvriježena nutricionistička preporuka za konzumacijom proizvoda bogatih polifenolima, što uključuje i grožđe te u umjerenim količinama i vino. Međutim, vino je proizvod koji nije namijenjen za konzumaciju u cijeloj populaciji te je u ovom diplomskom radu istražena i predstavljena alternativna opcija pića bogatog polifenolima koja bi bila pogodna i za skupine populacije poput starijih, djece i trudnica. Stoga je glavni cilj ovog istraživanja bio razvoj funkcionalnog proizvoda - soka od grožđa, obogaćenog polifenolima, kojeg mogu konzumirati sve skupine ljudi. Metodama masene spektrometrije i spektrofotometrijskim analizama je ispitan sastav polifenola soka, komine i obogaćenih sokova od grožđa. U ovom istraživanju su se koristili uzorci grožđa autohtonih bijelih sorti Kastavštine, za obogaćivanje sokova grožđa sa kominama, kako bi se bolje ispitao njihov, dosad neistraženi, polifenolni profil. Dobiveni rezultati ukazuju na to kako je međusobni utjecaj određenog soka i određene komine vrlo bitan, odnosno ovisno o porastu koncentracije željenog polifenola ključno je odabrati sortu komine za obogaćivanje soka od grožđa određene sorte. Time krajnji proizvod, obogaćeni sok ima specifičan polifenolni profil. Etanol, kao prihvatljivo otapalo u industrijskoj proizvodnji hrane, se pokazao učinkovit u ekstrakciji polifenola iz komine. Obogaćeni sokovi imaju visoki eksploatacijski potencijal u industriji te predstavljaju visokokvalitetan proizvod, koji široj populaciji može biti dobar izvor bioaktivnih spojeva. Također bi se ciljanim povezivanjem proizvodnje funkcionalnih sokova mogla pripremiti projekcija smanjenja organskog otpada i povećanja ekonomske isplativosti iskorištenja grožđa. Naposljetku bi proizvodnja autohtonih funkcionalnih proizvoda uvelike doprinijela regionalnom i nacionalnom gospodarskom rastu i razvitku.Polyphenols have very strong antioxidative, cardioprotective, neuroprotective and anticancerogenic activity, so accordingly, it is nutritionally recommended to increase consumption of polyphenol-rich food, such as for example grape products and moderately wine. Unfortunately, wine is a product that is not intended for the consumption of the entire population, and, within the presented research alternative polyphenol-rich beverage from grape has been studied and presented that might be appropriate for consumption in population groups of elderly, pregnant women and children. That is why the main goal of this research was development of a functional product – grape juice enriched with polyphenols, which is appropriate for consumption within all population groups. By use of mass spectrometry and spectrophotometry based methods, composition of polyphenols in juice and pomace as well as in enriched juices was examined. In this research samples of autochthonous white grapes from Kastav were exploited, to analyse their, until now, unexplored polyphenol profile, useful for future usage in enrichment of grape juice products. Results show that mutual influence of specific juice and specific pomace is highly relevant, in other words, rise in concentration of desired polyphenol is the key to the choice of specific sort if pomace for enrichment of the grape juice of specific sort. In such a way, a specific polyphenol profile for enriched product may be achieved. Furthermore, ethanol, as an appropriate solvent in industrial production of food, has shown to be efficient in extraction of polyphenols from the pomace. Enriched juices have great potential in industrial exploatation as they are a high quality end product adequate as a good source of bioactive compounds to the wider population. In addition, such targeted industrial development might be linked with development of projections for reduction of organic waste and increase in economic profitability. At last, production of autochthonous functional products might significantly contribute to the regional and national economic growth and development