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Vino je po končani alkoholni fermentaciji moten in nestabilen medij, ki ga je potrebno stabilizirati, da ohranimo njegovo kakovost do porabe. Namen magistrske naloge je bil spremljanje spontane beljakovinske in tartratne stabilizacije dveh mladih belih vin v treh različnih zorilnih posodah. Beljakovinsko in tartratno stabilnost vina smo spremljali z analizami vrednosti pH, skupnih (titrabilnih) kislin, posameznih organskih kislin, koncentracije mineralov kalija in kalcija, s toplotnim testom beljakovinske stabilnosti, s konduktometrično določitvijo tartratne stabilnosti in z merjenjem specifične električne prevodnosti. Na koncu praktičnega dela smo izvedli senzorično analizo vzorcev vina s petčlansko strokovno komisijo po 100-točkovni OIV metodi. Beljakovinska in tartratna stabilnost sta se vsem vzorcem vina med poskusom zorenja konstantno izboljševali. Na koncu poskusa sta se obema vinoma najbolj izboljšali z zorenjem v barrique sodih. Kisik pozitivno vpliva na doseganje tartratne stabilnosti in na doseganje beljakovinske stabilnosti, vendar v kombinaciji s spojinami iz lesa. Noben vzorec na koncu ni dosegel tartratne stabilnosti, saj je spontana stabilizacija dolgotrajen proces. Pri senzorični analizi vzorcev so najslabšo skupno oceno dosegli vzorci vina, ki so zoreli v barrique sodih. Wine is a turbid and unstable medium after completion of alcoholic fermentation, which needs to be stabilized in order to maintain its quality until consumption. The purpose of the master's thesis was to monitor spontaneous protein and tartrate stabilization of two young white wines in three different maturation vessels. Protein and tartaric stability of wine were monitored by analysis of pH value, total (titratable) acidity, individual organic acids, the concentration of two minerals, potassium and calcium, by heat test of protein stability, conductometric determination of tartrate stability and measurement of specific electrical conductivity. At the end of the practical part, we performed a sensory analysis of wine samples with a commission consisting of five experts using 100-point OIV method. Protein and tartaric stability was constantly improving during maturation of all wine samples. At the end of the experiment, both wines improved the most by maturing in barrique barrels. Oxygen has a positive effect on achieving tartrate stability and has a positive effect on achieving protein stability, but in combination with woods compounds. No sample ultimately achieved tartrate stability, as spontaneous stabilization is a lengthy process. The sensory analysis revealed the worst overall score was given to wine samples matured in barrique barrels.

Utjecaj srednje i jako paljenih bačvi od slavonske hrastovine na kakvoću crnih vina praćen je tijekom devet mjeseci dozrijevanja. U ovom radu detaljno su analizirani rezultati pojedinačnih polifenolnih spojeva, te je cilj bio utvrditi dinamiku promjene polifenolnog sastava pod utjecajem različitog stupnja paljenja hrastove bačve. Istraživana vina (od sorata 'Cabernet Sauvignon', 'Merlot' i 'Petit Verdot') dobivena su od grožđa uzgojenog na pokušalištu 'Jazbina', berba 2016., nakon fermentacija, koje su odvijene pod istim uvjetima svako se vino rastočilo u po dvije hrastove bačve različitog stupnja paljenja, srednjeg i jakog. Vina su dozrijevala devet mjeseci, te se nakon 1., 3., 6. i 9. mjeseca uzimalo uzorke za provođenje analize pojedinačnih polifenolnih spojeva primjenom tekućinske kromatografije. Utvrđeno je različito kretanje pojedinačnih polifenolnih spojeva, koja su promatrana i komentirana po skupinama, antocijani, fenolne kiseline, katehini i procijanidi. Antocijani u vinima od svih sorata i stupnja paljenja bačve pokazuju smanjenje koncentracija. Fenolne kiseline u vinima 'Cabernet Sauvignona' i 'Merlota' pokazuju smanjenje u trećem mjesecu dozrijevanja, dok se kod 'Petit Verdota', smanjnje javlja u šestom mjesecu. Galna se kiselina u svim vinima povećava, osim kod 'Petit Verdota'. Katehini i procijanidini u sva tri vina različito se kreću tijekom dozrijevanja. Medium and heavy toasting of slavonian oak barrels impact on quality of red wines which were observed during aging period of nine months. In this paper individual polyphenolic compounds were analysed and the aim was to determine trends in polyphenolic composition affected by level of barrel toasting. Wines used in this research were produced of grapes ('Cabernet Sauvignon', 'Merlot' and 'Petit Verdot') cultivated in experimental station ''Jazbina'', vintage 2016. After fermentations which were carried out under the same conditions, each wine was racked into two oak barrels of different toasting level. During nine months aging wine was sampled after 1st , 3rd, 6th and 9th month for individual polyphenolic analysis carried out by liquid chromatography. Various trends of individual polyphenolic compounds were observed and analysed in groups, anthocyanins, phenolic acids, catechins and procyanidins. Anthocyanin composition decreased in all wines. Phenolic acids in 'Cabernet Sauvignon' and 'Merlot' showed significant decrease in the third month of aging, while 'Petit Verdot's' decreased after sixth months. Gallic acid increase in all wines except 'Petit Verdot'. Catechins and procyanidins showed differnet trends during aging.