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The aim of this thesis was to determine how the application of ectomycorrhizal mycelium to the root of grapevine affects the chemical composition of wine 'Portugieser'. The experiment was set up in fall 2016. in 3 locations in the area of ZOI Plesivica, when the application of vaccine called „Mykoflor” of a company named Bio-buducnost d.o.o. from Zagreb was also performed. The vaccine was applied to 100 vines of variety 'Portugieser', with the same number of vines serving as a control. Analysis of chemical composition of wine was carried out after the harvest in 2018. at Department of Viticulture and Enology of Faculty of Agriculture in Zagreb in accordance with the O.I.V. (2001.) methods. By High Performance Liquid Cromatography (HPLC), single polyphenolic compounds were determined according to Tomaz and Maslov (2016.) method. Also, sensory evaluation of wine was performed using the method of 100 positive points. The results showed favorable effect of mycorrhiza on chemical composition of wines obtained from infected vines compared to the control wines. Positive effect was manifested in higher concentration of acids, sugar, increase in ash content and lower pH values. Application of mycorhizza also had a positive effect on the polyphenolic composition of wine.

Mikorizne gljive žive u simbiozi s korijenom viših biljaka, pa tako i vinove loze. Tijekom zajedničkog suživota, mikorizne gljive pomažu biljci u stjecanju vode i mineralnih hranjivih tvari iz tla, dobivajući za uzvrat produkte fotosinteze od biljke. Mikoriza igra ključnu ulogu u ciklusu hranjivih tvari u ekosustavu, a također štiti biljku od stresa iz okoliša pri čemu ujedno i povećava otpornost biljaka na štetnike i bolesti. Mikorizne gljive također imaju pozitivnu ulogu u prilagodbi biljke na nepovoljne uvjete tla. Štoviše, mikoriza kod inokuliranih trsova vinove loze može znatno povećati prinos i poboljšala kvalitetu grožđa.

U ukupnoj svjetskoj proizvodnji vina, pjenušava vina zauzimaju oko 10 % udjela, od čega se više od 80 % proizvodi u Europi. Istovremeno, prodaja pjenušavih vina je prema podacima iz 2019. najbrže rastući segment svjetske trgovine vina, s kontinuiranim globalnim rastom u posljednjih 15 g. Unazad desetak godina i Hrvatska bilježi značajan porast proizvodnje pjenušavih vina, pri čemu se, kao jedna od vodećih vinogradarsko-vinarskih županija, posebno ističe Zagrebačka županija. Senzorna svojstva vina, kako mirnih tako i pjenušavih, definirana su njihovim vanjskim izgledom, intenzitetom i čistoćom mirisa, čistoćom i punoćom okusa te općim dojmom koji proizlazi iz sveobuhvatnosti navedenih parametara. Aromatski profil pjenušavih vina kompleksno je svojstvo definirano velikim brojem hlapljivih spojeva koji mogu nastati u samoj bobici tijekom dozrijevanja grožđa, zatim u procesu primarne i sekundarne fermentacije te u uvjetima dozrijevanja vina, prije i nakon postupka degoržiranja. Cilj ovog istraživanja bio je definirati postojeća svojstva i kakvoću pjenušavih vina Zagrebačke županije kroz analizu pojedinačnih aromatskih spojeva metodom plinske kromatografije. Analize rezultata i stvaranje mirisnih serija za svaki uzorak, rezultirale su specifičnim aromatskim profilima te grupiranjem pjenušavih vina obzirom na različito područje (vinogorje) i metodu proizvodnje te korišteni sortiment., Sparkling wines production accounts for 10% of global wine production, with over 80% of production being linked to Europe. At the same time, sparkling wine trade and consumption are the fastest growing wine category with continuous increase in last 15 years. Over the last decade, Croatia has also recorded a significant increase in the production of sparkling wines, with the Zagreb County being one of the leading wine-growing counties in particular. The sensory properties of wines, both still and sparkling, are defined by their visual identity, intensity and aroma complexity, harmony, purity and fullness of taste and overall impression. The aromatic profile of a sparkling wine is a complex characteristic defined by a large number of volatile compounds that can be synthesized in the berry during the period of grape ripening, primary and secondary alcoholic fermentation in the bottle, and under the conditions of wine ageing, before and after disgorgement. The aim of this research was to define the existing properties and quality of Zagreb County sparkling wines through the analysis of individual aromatic compounds by gas chromatography in 34 different samples. Analyzes of the results and the creation of aroma series for each sample resulted in specific aromatic profiles and the grouping of sparkling wines by area (wine-growing hill), production method and assortment.

Aroma profiles and phenolic components of white wines made from ’Pošip’ and ’Škrlet’ (Vitis vinifera L.) both native Croatian, non-aromatic grape varieties enhances the knowledge about these varieties, prepared without maceration (control) and subjected to the pre-fermentative cold maceration (CM). Individual phenolic compounds in wines were determined by high- performance liquid chromatography (HPLC) system, while total phenolics and flavan-3-ols in wines were determined by spectrophotometric methods. CM had the significant impact on the total phenolic and flavan-3-ols composition of ’Škrlet’ wine. The significant increase of some individual phenolic compounds was observed in ’Pošip’ wine. Volatile aroma compounds in wines were determined by gas chromatography (GC) with the previous extraction on the solid phase micro extraction (SPME). The primary aroma compounds, i.e. terpenes were under the significant influence of CM process in ’Škrlet’ wine. Aroma profiles, based on the content of 24 specific compounds, grouped in eight aroma series that contribute to wine odor were developed. CM significantly increased five aroma series in ’Škrlet’ wine and only three in ’Pošip’ wine.

Malolactic fermentation (MLF) is a complex biochemical process playing an important role in the production of red wines. The main reasons for its implementation are the reduction of titratable acidity and the consequent increase of pH, microbiological stability of wine, and changes in aromatic and sensory properties of wine. The aim of this study was to determine the compatibility of yeast and bacteria used by different malolactic fermentation techniques and their influence on the fermentation duration, concentration of individual organic acids, aroma compounds, and on chemical and sensory properties of Teran wines. The experiment included control treatment (without MLF), spontaneous MLF, induced MLF at the beginning of alcoholic fermentation with simultaneous inoculation of yeast and bacteria (co-inoculation) and induced MLF after alcoholic fermentation (sequential MLF). In the co-inoculation treatment MLF had no negative effect on the alcoholic fermentation kinetic. Alcoholic fermentation was complete in all treatments. Co-inoculation resulted in a significantly shorter duration of the MLF process. In all MLF treatments, significant reduction of titratable acidity and the increase of pH values was noted. Wines of the spontaneous MLF treatment obtained the highest concentration of volatile acidity and ethyl acetate. In all MLF treatments a complete consumption of malic acid and a decrease in concentration of citric acid, total amount of higher alcohols, and acetaldehyde were observed. Furthermore, significantly higher concentrations of ethyl esters, diacetyl, acetoin, and 2,3-butanediol were present in wines from all MLF treatments.

Hrvatska se može s punim pravom smatrati vinogradarskom zemljom s dugom i bogatom tradicijom proizvodnje vina. Zahvaljujući raznolikosti okolišnih uvjeta, prisutnih na različitim uzgojnim područjima, dugoj povijesti i mnogobrojnim sortama u uzgoju, teško je dati kratak opis te proizvodnje kao i jasno definirati trendove. Svakako se može reći kako se radi o proizvodnji koju odlikuje veliko bogatstvo i raznolikost, koja ima neke svoje nedostatke, ali istovremeno nudi velike mogućnosti. Suvremeni razvoj vinogradarsko-vinarske proizvodnje u Hrvatskoj, koji započinje potkraj 90-ih godina prošlog stoljeća, do danas je rezultirao relativno velikim brojem malih i srednjih proizvođača koji njeguju raznolikost i specifičnosti pojedinih područja. S obzirom na relativno malu proizvodnju, taj segment proizvođača često nudi visokokvalitetna vina, pri čemu njihovu vrijednost nastoje dodatno povećati naglašavajući tradiciju, izvornost i općenito specifičnost. Svega je nekoliko velikih proizvođača koji su uspješno preživjeli tranziciju, prilagodili se modernim trendovima i nastoje zadržati svoj dio tržišta, nudeći primarno vina s relativno dobrim odnosom cijene i kvalitete. Pritom se često moraju boriti s velikim pritiskom konkurencije koja je prisutna u spomenutom segmentu, kako iz ostalih zemalja EU-a, tako i iz zemalja Novoga svijeta. Graševina je već dugo najvažnija sorta, i zauzima otprilike četvrtinu svih vinogradarskih površina, a slijede malvazija istarska i plavac mali. Autohtone sorte prepoznate su već duže vrijeme kao vrlo važne, kako trenutačno, tako i za budući razvoj vinogradarstva u Hrvatskoj. S obzirom na to, velika se pažnja pridaje unaprjeđenju njihova uzgoja. Postoje brojni problemi u tom kontekstu, a među najvećima je nedostatak kvalitetna sadnog materijala autohtonih sorata, što je posebno izraženo kod onih rijetkih, slabije zastupljenih. Slijedi i problem iznimno nepovoljna sanitarnog statusa proizvodnih nasada, tj. visokog stupnja zaraženosti gospodarski značajno štetnim virusima, kao i nedovoljne prilagodbe ampelotehničkih zahvata i enoloških postupaka za iskorištenje punog kvalitativnog i kvantitativnog potencijala te grupe sorata. Zbog rješavanja tih problema već se dugo provode različite aktivnosti u vidu projekata klonske i sanitarne selekcije, kojima se nastoji unaprijediti genska osnova autohtonih sorata i uspostaviti sustav proizvodnje zdravog i kvalitetnog sadnog materijala. Također, provode se različita primijenjena istraživanja zbog unaprjeđenja i maksimalnog iskorištenja potencijala vinogradarske i vinarske proizvodnje autohtonih sorata. Posljednjih nekoliko godina odvijaju se velike investicije potpomognute sufinanciranjem iz EU-fondova, posebno za mlade proizvođače. To je imalo pozitivan utjecaj na brojne mlade proizvođače koji su naslijedili ili pokrenuli proizvodnju i zadržali se u ruralnim područjima. Unatoč negativnu utjecaju pandemije koronavirusa COVID-19 tijekom posljednjih godinu dana, u nadolazećem se razdoblju očekuje daljnji napredak ovoga sektora ako se situacija normalizira.

Suočavajući se sa sve drastičnijim utjecajem klimatskih čimbenika na kemijski sastav grožđa, enologija traži i proučava nove metode u tehnologiji proizvodnje vina, posebice bijelih, kako bi se očuvale primarne arome te postigla ravnoteža između alkoholne jakosti i ukupne kiselosti. Kao jedno od rješenja nudi se primjena ne- Saccharomyces kvasaca. U ovom istraživanju analiziran je utjecaj sekvencijalne inokulacije komercijalnih sojeva Torulospora delbrueckii i Lachancea thermotolerans sa sojem kvasca Saccharomycem cerevisiae na vino ´Malvazija istarska´. Istraživanje je obuhvatilo inokulacije mošta s ne-Saccharomyces kvascima, a 48 h kasnije i sa sojem S. cerevisae te kontrolnu varijantu isključivo sa S. cerevisae. Ne-Saccharomyces kvasci utjecali su značajno na koncentraciju alkohola, mliječne kiseline te pH vrijednost. Fermentacija sa S. cerevisiae utjecala je na višu koncentraciju ukupnih aromatskih spojeva u vinu. Intenziteti boje i mirisa najbolje su ocijenjeni u kontrolnom uzorku, a metodom redoslijeda najbolje je rangirana ´Malvazija´ iz tretmana T. delbrueckii/ S. cerevisiae., As we face drastic climate change, new methods are being sought in the technology of wine production, especially in production of white wines, in order to preserve the primary aromas and achieve the desired balance of alcohols and acids. As a potential solution the use of non-Saccharomyces yeasts whose metabolism differs from Saccharomyces yeasts is suggested. In this study the influence of sequential inoculation of Torulospora delbriueckii and Lahancea thermotolerans with Saccharomyces cerevisiae on Malvasia istriana wine was studied and analyzed. Malvasia Istriana is the second most widespread white grape variety in Croatia and thus one of the most economically important varieties. The study included inoculations of must with non-Saccharomyces yeasts, and 48 h later with S. cerevisae QA23 strain and fermentation exclusively with S. cerevisae QA23. Non-Saccharomyces yeasts contributed to lower ethanol concentration, especially T. delbrueckii which in co-culture with S. cerevisae was not able to ferment a significant amount of fructose and L. theromotolernas by converting sugar to lactic acid. Although differences within the aromatic profile were observed, none of the non-Saccharomyces strains significantly affected the overall wine aroma. Although the aroma, color and color intensity were best evaluated in the sample produced with the S. cerevisiae strain, the best ranked wine was Malvasia T. delbrueckii/S. cerevisiae.

The effect of four different winemaking processes on phenolic compounds, macro- and microelements, and taste sensory attributes of Teran red wines was studied. The study covered seven days of maceration as a control (TM7), prolonged 10-day maceration (TM10), prolonged post-fermentative 21-day maceration (TM21), and 48-h pre-fermentative maceration heating at 45 °C followed by eight-day standard maceration (TPHT). Phenolic compounds were analyzed using high-performance liquid chromatography with UV–Vis diode array and fluorescence detection. Analysis of macro- and microelements was conducted by inductively coupled plasma - optical emission spectrometry. Sensory profiles of wine samples were obtained using quantitative descriptive analysis and the 100-point O.I.V./U.I.O.E. method. The results showed a significant increase of 25% in total flavan-3-ols content in TM21 wine. The concentrations of hydroxybenzoic acids increased significantly upon TM21 and TPHT treatment, while particular hydroxycinnamic acids showed a significant increase after TPHT treatment. The obtained results showed differences in the content of macro- and microelements, with significantly higher values of particular elements in TM21 and TPHT wines. Sensory analysis results corresponded to the chemical content of the wines to a great extent. The findings showed that TM21 and TPHT treatments have a positive influence on the taste attributes of the investigated wines.

Sulfur dioxide (SO2) is widely the most used enological additive with reductive, antiseptic and dissolving properties. According to increasing health concerns and the gradual decrease in total SO2 concentrations allowed in wine, alternative and supplementary agents for preservation are being investigated. For this reason, the current study was focused on the impact of different commercial reductive agents on white wine antioxidant activity and chemical composition. The effect of additives that combine sulfites, ascorbic acid and enological tannins were compared against standard 5% sulfurous acid (H2SO3) during the pre-fermentative treatments of Sauvignon Blanc must (Vitis vinifera L.). The basic parameters of quality, free amino-nitrogen and total polyphenoliccompounds in must were analyzed. Gas chromatography and spectrophotometric methods were used to investigate the overall volatile composition, antioxidant and chromatic parameters in wines. The obtained results undoubtedly pointed out the positive effect of sulfuric acid on the fermentation dynamics. Furthermore, application of combined reducing additives with potassium metabisulfite, L-ascorbic acid, gallotannins and ellagitannins, resulted in a higher antioxidant capacity and increased concentration of aromatic compounds and their odor activity values in Sauvignon Blanc wine.

Senzorna svojstva vina, kako mirnih tako i pjenušavih, definiraju se njihovim vanjskim izgledom, intenzitetom i čistoćom mirisa, harmoničnošću, čistoćom i punoćom okusa te općim dojmom koji proizlazi iz sveobuhvatnosti navedenih parametara. Proizvodnja pjenušavih vina klasičnom metodom podrazumijeva provođenje sekundarne fermentacije u boci što omogućava kontakt vina s talogom kvasaca određeni vremenski period čime se direktno utječe na aromatski profil i kakvoću okusa. Obzirom na sorpcijski kapacitet stanične stjenke kvasca, tijekom dozrijevanja može doći do značajnih razlika u koncentracijama pojedinih hlapivih spojeva, a samim time i intenziteta te kakvoće mirisa pojedinog pjenušca. U definiranju kakvoće pjenušavih vina, uz mirisna i okusna svojstva, vrednovanje vanjskog izgleda ima posebnu važnost obzirom na perlanje kao čimbenik koji ga razlikuje od mirnih vina, a čini i značajnu razliku među pojedinim pjenušcima. Cilj ovog istraživanja bio je utvrditi razlike u vanjskom izgledu, intenzitetu, duljini i kakvoći perlanja, kakvoći i postojanosti mirisa i okusa te općem dojmu kod 10 bijelih i 5 rosé pjenušavih vina različite duljine dozrijevanja., The sensory properties of still and sparkling wines are defined by their appearance, intensity and purity of smell, harmony, purity and fullness of taste, and the general impression derived from these parameters. The production of sparkling wines by classical method implies the implementation of secondary fermentation in the bottle, which allows the contact of the wine with yeast lees for a longer period of time, enabling direct effect on the aromatic profile and the taste quality of the end product. During maturation due to the sorption capacity of the cell wall of the yeast, significant differences can be found in the concentrations of the individual volatile compounds and hence the intensity and quality of the scent of each sparkling wine. In addition to the aromatic and taste properties, the evaluation of the external appearance in the definition of the quality in the sparkling wines is of additional importance and can vary greatly from sparkling wine to sparkling wine. Therefore, the aim of this study was to determine the differences in the intensity, length and quality of the foam and the external appearance, the aromatic profile, the quality and the persistence of taste and the general impression among the 5 rosés and 10 white sparkling wines with regard to the different length of maturation.

Hladna maceracija se sve više nameće kao jedan od uobičajenijih tehnoloških postupaka u proizvodnji bijelih vina čime se utječe na kompleksnost arome i punoću okusa vina. Područje uzgoja autohtone sorte ´Grk´ (Vitis vinifera L.) usko je vezano uz otok Korčulu pri čemu je najpoznatiji vinogradarski položaj u Lumbardi. Dosadašnja tehnologija proizvodnje bijelih vina na tom području bila je vezana isključivo uz postupak brze prerade ili uz tradicionalnu maceraciju u nekontroliranim uvjetima. Cilj ovoga rada je primjenom kontrolirane hladne maceracije i različitih selekcioniranih sojeva kvasaca definirati osnovna fizikalno-kemijska svojstva, aromatski profil te senzorna svojstva vina Grk. U istraživanju je korišteno grožđe sorte ´Grk´, berbe 2014. godine te komercijalni sojevi kvasaca Lalvin EC 1118 i Lalvin QA23. Neposredno nakon procesa runjenja i muljanja ohlađenoga grožđa, dobiveni masulj maceriran je na temperaturi od 10 °C u trajanju od 6 sati. Nakon procesa taloženja, moštovi su inokulirani selekcioniranim kvascima te je provedena alkoholna fermentacija u kontroliranim uvjetima. U dobivenim vinima je provedena osnovna fizikalno-kemijska analiza prema metodama OIV-a, analiza aromatskih spojeva uz pomoć plinske kromatografije te senzorno ocjenjivanje.

According to many literature data, it can be concluded that with a more than 6000-year history starting from Georgia wine or from the chemical point of view fermented grape juice is one of the world’s oldest fermented beverage. Wine composition and quality are influenced by many factors such as grape variety, environmental conditions (climate, soil properties, soil water, terrain), as well as fermentation conditions mainly determined by fermentation temperature and yeast species selection. Until today more than 800 volatile compounds have been identified at the wide range of chemical groups concentration levels. Among them, three major groups can be pointed out as primary (varietal), secondary (fermentative), and tertiary (aging) wine aroma. The combination of varietal and fermentative aroma compounds are found to be one of the first factors influencing wine quality and the choice of yeast species and selected strains are singled out as one of a determinant in defining the concentration of these volatile compounds. Nowadays wine producers have tried to avoid the uniformity of product searching, the way to produce more complex wines with distinctive aroma profile, which can be achieved by the use of non-Saccharomyces species. There are numerous papers concerning the composition and content of aroma compounds in different grape varieties and wines produced with different yeasts, but till date, there is no review article that unifies these data. Thus, the aim of this chapter is to unify the known data concerning the influence of selected yeast species in single, simultenouos, and sequential fermentations on the content and composition of aroma compounds.

Four terroirs where cv. Malvasia Istriana is grown under equal viticultural practices and climatic conditions, but on different soil types, were studied. Grape juice samples were taken during ripening at three grapevine growth stages (S35 – berries begin to colour and enlarge ; S36 – berries with intermediate Brix values ; and S38 – berries harvest ripe). Malvasia Istriana grape juice showed a specific free amino acid profile during all three grapevine growth stages, where arginine was the most abundant free amino acid, followed by alanine, threonine, tyrosine, aspartic acid, serine, histidine and glutamic acid. Leucine was the least abundant free amino acid on all studied terroirs at all grapevine growth stages. Total free amino acids decreased at S38, compared to both S35 and S36, on all terroirs, except Fiorini terroir where total free amino acids concentration at S38 was significantly lower compared to S36, but significantly higher compared to S35.

Tijekom berbe 2017. proizvedena su četiri vina ´Chardonnay´ uz upotrebu različitih komercijalno dostupnihsojeva Saccharomyces cerevisiae i bayanus kvasaca te je uspoređen njihov aromatski profil. Primjenom ekstrakcije na čvrstoj fazi te vezanim sustavom plinska kromatografija- spektrometar masa, u vinima je identificirano oko 70 hlapljivih spojeva. Analizirani spojevi, podijeljeni u 7 kemijskih grupa, značajno su utjecali na senzorni profil vina i njihovu različitost. Rezultati su pokazali značajan i pozitivan utjecaj korištenih sojeva kvasaca na neke grupe spojeva koji doprinose kakvoći vina, poput etil-estera, izoamil i izobutil-acetata, nekih viših alkohola te monoterpena (linalol, citronelol i geraniol). Određena je i aktivna mirisna vrijednost (OAV) pojedinih aromatskih spojeva koji su prema sličnosti deskriptora grupirani u aromatske serije poput voćne, cvjetne, začinske i maslačne, što je omogućilo i opisno definiranje aromatskog profila svakog vina., During the vintage 2017 four wines obtained by fermenting Chardonnay musts with commercial starter cultures of Saccharomyces cerevisiae and bayanus yeast strains were compared in terms of their volatile aroma compounds composition. An easy handle methodology Solid Phase Extraction Gas Chromatography Mass Spectrometry-based enabled the identification of almost 70 volatile compounds. These aroma compounds, arranged in seven chemical groups strongly influenced the sensory profile of each wine allowing their differentiation. The results revealed marked influence and positive contribution of yeast strains that were used on several wine quality contributors such as ethyl esters, isoamyl and isobutyl acetate, some higher alcohols and monoterpenes like linalool, citronellol and geraniol. Odor activity value of aroma compounds (OAV) was determined and by grouping the once with similar descriptors into aromatic series such as fruity, floral, spicy and buttery a descriptive organoleptic profile of each wine was established.

Utjecaj srednje i jako paljenih bačava (225 L) od slavonske hrstovine na kakvoću crnih vina praćen je tijekom 9 mjeseci dozrijevanja. Cilj istraživanja bio je utvrditi razlike u kemijskom sastavu i senzornim svojstvima vina ´Cabernet Sauvignon´, ´Merlot´ i ´Petit Verdot´. Promjene u kemijskom sastavu vina praćene su metodom plinska kromatografija-masena spektrometrija (GC-MS) temeljem uzorkovanja vina svakih 3 mjeseca. Utvrđen je različiti intenzitet ekstrakcije polifenolnih spojeva, ovisno o jačini paljenja bačava koji je najviše utjecao na koncentracije eugenola, gvajakola, vanilina te cis i trans-hrastovog laktona. Na koncentracije ostalih laktona (γ-heksalakton, γ-nonalakton, γ-dekalakton) veći utjecaj je imala sorta u odnosu na jačinu paljena i vrijeme dozrijevanja. Ekstrakcija hlapivih spojeva iz drva bila je različita među ispitivanim vinima pri čemu je u vinu ´Cabernet Sauvignon´ bila najintenzivnija. Razlike su utvrđene i u koncentracijama hlapivih fenola. Tako su vina ´Petit Verdot´ imala najnižu koncentraciju etil-fenola i etilgvajakola dok je veća koncentracija zabilježena u vinima ´Cabernet Sauvignon´ neovisno o jačini paljenja. Prema rezultatima senzornog ocjenjivanja bolja su vina dozrijevana u srednje paljenim bačvama u odnosu na ona iz jako paljenih, pri čemu je ukupno najbolje ocijenjeno vino sorte ´Merlot´., The wood-related volatile profile of red wines aged in medium and hard toasted Croatian oak barrels was studied by GC–MS method. The objective of this study was to describe the differences in chemical composition and sensory properties of the 'Cabernet Sauvignon,' 'Merlot' and 'Petit Verdot' wines during the nine months aging period. Different rates of extraction have been observed, depending on the toasting method used. The toasting level influenced more considerably eugenol, guaiacol, vanillin and cis and trans-oak lactone concentrations. Among other lactones analysed (γ-hexalactone, γ-nonalactone, γ-decalactone), grape variety had more pronounced influence than toasting level and aging period. The accumulation of oak compounds was different, depending on the wine aged in the barrels with the extraction rate being more favoured in the Cabernet Sauvignon wines. Marked difference was noted in the ethyl phenols concentrations among tested wines. 'Petiti Verdot' contained the lowest levels of both phenols (ethyl phenol and guaiacol) while higher concentrations were noted in Cabernet Sauvignon wines regardless of the toasting level. Sensory evaluation pointed out better overall quality of wines aged in medium toasted barrels while among varieties, best results were achieved in Merlot wines.

Utjecaj srednje i jako paljenih bačava (225 L) od slavonske hrstovine na kakvoću crnih vina praćen je tijekom 9 mjeseci dozrijevanja. Cilj istraživanja bio je utvrditi razlike u kemijskom sastavu i senzornim svojstvima vina ´Cabernet Sauvignon´, ´Merlot´ i ´Petit Verdot´. Promjene u kemijskom sastavu vina praćene su metodom plinska kromatografija-masena spektrometrija (GC-MS) temeljem uzorkovanja vina svakih 3 mjeseca. Utvrđen je različiti intenzitet ekstrakcije polifenolnih spojeva, ovisno o jačini paljenja bačava koji je najviše utjecao na koncentracije eugenola, gvajakola, vanilina te cis i trans-hrastovog laktona. Na koncentracije ostalih laktona (γ-heksalakton, γ-nonalakton, γ-dekalakton) veći utjecaj je imala sorta u odnosu na jačinu paljena i vrijeme dozrijevanja. Ekstrakcija hlapivih spojeva iz drva bila je različita među ispitivanim vinima pri čemu je u vinu ´Cabernet Sauvignon´ bila najintenzivnija. Razlike su utvrđene i u koncentracijama hlapivih fenola. Tako su vina ´Petit Verdot´ imala najnižu koncentraciju etil-fenola i etilgvajakola dok je veća koncentracija zabilježena u vinima ´Cabernet Sauvignon´ neovisno o jačini paljenja. Prema rezultatima senzornog ocjenjivanja bolja su vina dozrijevana u srednje paljenim bačvama u odnosu na ona iz jako paljenih, pri čemu je ukupno najbolje ocijenjeno vino sorte ´Merlot´.

Na području vinogorja Klanjec temeljem ampelotehničkih istraživanja hrvatskih autohtonih sorata vinove loze izdvojena je sorta Sokol koja se po povijesnim navodima uzgaja na ovom području od 17.st. Sorta ima visok kvalitativni potencijal, a daje vina iznadprosječne kvalitete. Vina karakterizira posebna sortna aroma, obično srednjeg intenziteta. Za potpunu ocjenu sorte ne postoji dovoljno praktičnih iskustava. Sorta Sokol je u procesu revitalizacija, a glavni cilj je obnoviti proizvodnju vina navedene sorte koja je svojevremeno imala značajno mjesto u vinskoj ponudi klanječkog kraja. U ovome radu prikazani su rezultati fizikalno-kemijske analize vina iz tri uzastopne godine berbe (2012., 2013., 2014.) te su međusobno uspoređeni s ciljem procjene potencijala sorte. Po dobivenim rezultatima fizikalno-kemijske analize vina iz sve tri godine berbe moglo bi se svrstati u kategoriju vrhunskih vina. Na osnovu provedenih istraživanja kroz tri godine berbe vidljivo je da sorta Sokol ima veliki potencijal i opravdanost za sadnju na prostorima Klanječkog vinogorja, gdje za sada daje pozitivne rezultate., During ampelotechnological research of Croatian autochthonous grapevine varieties in Klanjec winegrowing area, variety Sokol was isolated. According to the historical allegations Sokol variety was grown in this area since the 17th century. This variety has a high quality potential, and provides outstanding quality wines. The wines are characterized by a special varietal aroma, usually of medium intensity. For a full evaluation of the variety there is a lack of practical experience. Currently, the process of the revitalization of Sokol is active whose goal is to rebuild the production of Sokol wine, which once had a significant place in the Klanjec wine list. In this paper the results of physico-chemical analysis of wines from three years of harvest (2012, 2013, 2014) were presented and compared with each other in order to evaluate the potential of Sokol variety. According to their physical - chemical properties wines from all three years could be included in premium wines category. Based on research conducted during three years of harvesting, it is evident that the variety Sokol has great potential and justification for planting in the area of the Klanjec vineyards, where for now giving positive results.

Continental Croatia wine region and especially Kutjevo vineyards are famous for their predicate wines production and quality. The most common grape varieties used there for different types of predicate wine are Welsch Riesling and Traminer. Ice wines, selected harvest wines and dry berry selection wines from different harvest years were examined by HPLC method to determine organic acids composition. The oldest sample was Traminer selected harvest from vintage year 1990, while the youngest wine was Traminer ice wine from harvest 2011. The dominant organic acids in all analyzed wines were tartaric, malic, citric and galactaric, ranged from 0.09 to 2.98 g/L. In most wines the difference in concentration of glucuronic, galacturonic and gluconic acids was established. The highest content of glucuronic acid was 58.4 mg/L in Traminer dry berry selection 2011. Galacturonic acid dominated in the same wine (924 mg/L), just like gluconic acid (141 mg/L).

Rok berbe je važan čimbenik u proizvodnji crnih vina visoke kakvoće, prvenstveno zbog značajnog utjecaja na polifenolnu zrelost grožđa. Međutim, tehnologija prerade grožđa, također, ima važnu ulogu. Klasičnom se metodom prerade, koja podrazumijeva istovremeno protjecanje maceracije i alkoholne fermentacije, obično proizvode vina s većom koncentracijom polifenolnih spojeva, posebice flavanola, koji mogu utjecati i na izraženiju gorčinu i astringentnost. Primjenom se postupka hladne maceracije masulja moguproizvesti vina s više antocijana, koji pridonosi intenzitetu boje te izraženije arome uslijed bolje ekstrakcije sortnih aroma i prekursora arome. Istovremeno, zbog nižih temperatura, dolazi do manje ekstrakcije grubih flavanola. Primarni je cilj i svrha ovog istraživanja bilo utvrditi utjecaj roka berbe i temperature maceracije na polifenolni sastav grožđa i kakvoću vina sorte Frankovka u proizvodnim uvjetima vinogradarske podregije Podunavlje, vinogorja Srijem. Istraživanje je provedeno 2011. godine, pri čemu su analizirani ukupni fenoli, flavonoidi, flavanoli i antocijani, sastav pojedinačnih organskih kiselina te osnovni kemijski sastav vina. Različiti su rokovi berbe utjecali na sastav i koncentraciju polifenolnih spojeva. U grožđu su Frankovke iz drugog roka berbe (5.10.) izmjerene veće koncentracije ukupnih polifenola i antocijana. Utvrđeno je da su rok berbe i tip maceracije utjecali na razlike u osnovnom kemijskom sastavu vina te koncentracijama fenolnih spojeva. U vinima je prvog roka berbe (20.09.) utvrđen veći sadržaj ekstrakta bez šećera, pepela, FAN-a i ukupne kiselosti, kao i vrijednosti ukupnih polifenola, ukupnih antocijana i ukupnih flavanola u odnosu na drugi rok berbe, neovisno o provedenom tipu maceracije. U vinima dobivenim klasičnom metodom utvrđena je veća koncentracija vinske kiseline. Prema većem se sadržaju ukupnih antocijana izdvojilo vino hladne maceracije iz prvog roka berbe., The phenolic maturity of grapes is greatly affected by the harvest time which is, along with wine technology, one of the most important factors in the production of high quality red wine. The traditional production of red wine that combines simultaneous fermentation with maceration process results in wine enriched with polyphenolic compounds, especially flavanols that can contribute to greater bitterness and astringency. Applying cold maceration before fermentation can result in wine with more anthocyanins that influence the colour intensity and result in more intensive aroma due to more sufficient extraction of primary aromas and aroma precursors. At the same time, lower temperatures reduce the extraction of harsh flavanols. The objective of this research was to determine the influence of harvesting date and maceration temperature on polyphenolic maturity and the quality of Frankovka grapes and wines in the winegrowing area of Srijem, the sub region of Podunavlje. The study was carried out on the 2011 vintage. Total phenols, flavonoids, flavanols, anthocyanins, individual organic acids and general wine composition were analyzed. Different harvesting dates affected both polyphenolic composition and concentration. Based on the results, we have determined that the highest concentration of total phenols and anthocyanins was on the second harvesting date (5 October). Harvest date and different maceration type affected the general and polyphenol composition of wine. Wines produced from grapes picked on the first harvesting date (20 September) had higher levels of extract without sugar, ash, FAN and total acidity, as well as total phenols, flavanols and anthocyanins concentrations, regardless of the type of maceration. Wine produced using the traditional method had higher concentration of tartaric acid. The wine produced from grapes picked on the first harvesting date on which cold maceration was applied had higher levels of total anthocyanins.

Different clones from a single grape variety can differ in their productive characteristics and their ability to produce wines with different organoleptic characteristics. The ammonium ions and free amino acids are the main sources of nitrogen for Saccharomyces cerevisiae and thus the concentration of nitrogen compounds in the must can significantly affect the wine quality. ‘Kraljevina’ is well known Croatian autochthonous variety traditionally grown in Northwest Croatia. The clonal selection was started in 2003, and in the period 2011-2012 the evaluation of nine clones of ‘Kraljevina’ grape variety (VV-360, VV-482, VV-486, VV- 438, VV-434, VV-479, VV-423, VV-406, VV-483) was conducted. The grapes of the clones tested were harvested on the same day and the obtained juices were filtered and stored for further amino acids analysis. The obtained results pointed to significant diverseness and strong clonal influence on amino acid composition between tested clones. The most abundant amino acid in all clones was arginine ranging from 197.07 to 438.36 mg/L, while the smallest differences were noticed in isoleucine, cysteine, valine and phenylalanine concentrations. The total amino acids concentration ranged from 492.7 mg/L in VV-406 clone to 952.04 mg/L in VV-360 ‘Kraljevina’ clone.

Većina hrvatskih vina od bijelih autohtonih sorata proizvodi se standardnom preradom grožđa, bez maceracije. Iako su crna vina poznata po bogatstvu fenolnim spojevima, što je posljedica i tehnologije proizvodnje, koncentracija navedenih spojeva u bijelim vinima također može biti značajna s obzirom na sortu i primijenjenu tehnologiju u proizvodnji vina. S obzirom na suvremene trendove istraživanja vina koja se temelje na proučavanju fenolnih spojeva koji blagotvorno djeluju na ljudsko zdravlje - cilj našeg istraživanja bio je pridonijeti spoznaji o vrijednosti autohtonih sorata koje su nedovoljno istražene u tom smislu. U istraživanju su korištene sorte Kraljevina, Škrlet, Malvazija, Pošip i Maraština. Vino svake sorte proizvedeno je standardnom tehnologijom za bijela vina (varijanta A) i hladnom maceracijom masulja od 6 sati na 10°C (varijanta B). Utjecaj hladne maceracije na osnovni kemijski sastav mošta i vina kao i koncentraciju ukupnih fenola i flavanola razlikovao se s obzirom na istraživanu sortu. Najveća koncentracija ukupnih fenola pronađena je u vinu sorte Škrlet, a najveće razlike između varijanti A i B zabilježene su kod vina Kraljevina, Škrlet i Malvazija. Senzorna analiza provedena je metodom 100 bodova, pri čemu su bolje ocijenjena vina Pošip, Škrlet i Maraština dobivena procesom hladne maceracije., Most Croatian autochthonous white wines are produced by standard technology for white wines, without maceration process. Even though richness of polyphenol compounds is correlated with red wines, white wines can also be a source of polyphenols, concentrations mostly dependent of winemaking technology used. A positive influence of polyphenol compounds on human health is well known, and because of that our main goal was to determine their concentrations in Croatian autochthonous wines. In the research five cultivars were used: Maraština, Kraljevina, Pošip, Škrlet and Malvazija istarska. Each wine was produced without maceration process and with cold maceration process lasting for 6 hours on 10 °C. The influence of cold maceration for every investigated cultivar was noted in basic chemical composition and total phenol and flavan-3-ol concentrations. Škrlet wines had the highest concentrations of total phenols, while the most significant differences between the not macerated and macerated wines was noted in Kraljevina, Malvazija and Škrlet wines. Sensory analysis of produced wines by 100 positive score method pointed out Pošip, Škrlet and Maraština wines produced by cold maceration.

Skin maceration contact time is essential winemaking technique to affect anthocyanin concentration and high quality of red wines. The aim of this work was to investigate the changes in basic composition, anthocyanin profile and sensory properties of Blatina wines obtained with skin contact time from 4, 8, 12 to 16 days. Results indicate that longer period of maceration positively influenced the quality of Blatina wines. Blatina wines obtained by 12 or 16 days of maceration presented a significant increase of the dry extract, ash, total phenol and pH value. It was observed that the concentration of total and individual anthocyanins significantly increased reaching a maximum value within 12 days of the skin maceration. In all wines, the dominant anthocyanin was malvidin 3-glucoside. Best organoleptic properties were observed in the wines macerated for 16 days.

Kultivar Kraljevina hrvatska je autohtona sorta koja se tradicionalno uzgaja na području sjeverozapadne Hrvatske. Od 2003. godine taj je kultivar uključen u postupak klonske selekcije unutar projekta “Klonska selekcija cv. Kraljevina”. U početnoj fazi istraživanja odabrani su i temeljem pozitivne fenotipske varijabilnosti izdvojeni trsovi na kojima su tijekom idućih godina provođena fenotipska opažanja, a temeljem dobivenih rezultata 24 elitna matična trsa vegetativno su razmnoženi i posađeni u kolekciju klonskih kandidata u Psarjevu Gornjem. U 2011. godini 9 klonskih kandidata Kraljevine zasebno je obrano te je provedena mikrovinifikacija u kontroliranim uvjetima uz korištenje dvaju komercijalnih kvasaca i to Anchor VIN13 te Uvaferm Affinity. U dobivenim vinima provedena je osnovna kemijska analiza, određene su pojedinačne organske kiseline te su na kraju vina senzorno ocijenjena., Kraljevina cultivar is an autochthonous Croatian variety which is traditionally cultivated at the area of north-western Croatia. That cultivar has been included into the procedure of clonal selection within the project “Clonal selection cv. Kraljevina” since 2003. During the initial stage of research there were selected and, based on positive phenotypic variability, singled out vines which were used for phenotypic observations in the following years. Based on the obtained results of 24 elite mother vines, they were vegetatively propagated and planted in the collection of clone candidates in GornjePsarjevo. Nine clone candidates of Kraljevina were separately harvested in 2011 and microvinification was conducted in controlled conditions by using two commercial yeasts, Anchor VIN13 and Uvaferm Affinity. In the obtained wines there were conducted the basic chemical analysis, individual organic acids were determined and sensory evaluation of wines was performed.