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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.

Optimalan izbor filtera značajno utječe na zadržavanje određenih svojstava vina, a posebno kod aromatičnih vina. Tijekom istraživanja primijenjeni su pločasti filteri proizvođača “Seitz” različitih stupnjeva filtracije; K300, K200, K100. Korištene filter ploče su dimenzija 20x20 cm. Za filtriranje su korištena sljedeća vina; traminac i mješavina crnih vina (pinot crni, frankovka, zweigelt). Vina su proizvedena 2011. godine. Nakon filtracije spomenutih vina različitim filter pločama obavljeno je organoleptičko ocjenjivanje vina., The optimal choice of filters significantly influences maintaining certain characteristics of wine, especially with aromatic wines. During the research there were applied plate filters of the producer “Seitz” of different filtration degrees; K300, K200, K100. The dimension of the used filter sheets was 20x20 cm. The following wines were used for filtering: traminer and a mixture of red wines (pinot noir, frankovka, zweigelt). The wines were produced in 2011. After filtration of the above-mentioned wines by different filter sheets, a sensory evaluation was performed.

Antocijani su pigmenti crvene boje smješteni uglavnom u kožici bobice crvenog grožđa te pridonose boji crvenih vina. Njihova koncentracija u vinima ovisi o: sorti, području uzgoja, tehnikama vinifikacije. Najzastupljeniji antocijan u vinima proizvedenim od grožđa Vitis vinifera L. je u pravilu malvidin-3- monoglukozid. Utjecaj na ekstrakciju i degradaciju antocijana mogu imati i Saccharomyces cerevisiae kvasci. Identifikacija antocijana u vinima Teran i Cabernet sauvignon berbe 2009. provedena je tehnikom tekućinske kromatografije visoke djelotvornosti. Istraživan je utjecaj tri komercijalna Saccharomyces cerevisiae kvasca (Uvaferm BDX, D254 i Fermol Premier Cru) na koncentraciju antocijana. Rezultati istraživanja pokazali su da kvasci Uvaferm BDX i D254 ekstrahiraju više aciliranih i neaciliranih antocijana., Anthocyanins are red, blue and purple pigments located mainly in the skin of red grape berries and contribute to the color of red wines. Their concentration in wine depends on variety, ecological conditions, growing and vinification techniques. The most common anthocyanin in red wines made from Vitis vinifera L. grapes is generally malvidin-3-monoglucoside. Saccharomyces cerevisiae yeast may have the impact on the extraction and degradation of anthocyanins. Identification of anthocyanins in wines Cabernet Sauvignon and Teran in harvest 2009 was analyzed by the technique of high performance liquid chromatography. The effects of three commercial Saccharomyces cerevisiae yeasts (BDX Uvaferm, D254 and Fermol Premier Cru) on the concentration of anthocyanins were investigated. The results showed that yeasts Uvaferm BDX and D254 extracted more non- acylated and acylated anthocyanins.

Jabučno-mliječna fermentacija (JMF) je proces biološkog otkiseljavanja vina u kojem se dikarboksilna L-jabučna kiselina pretvara u monokarboksilnu L-mliječnu kiselinu i ugljik(IV)-oksid. JMF provode bakterije mliječne kiseline (BMK) iz rodova Oenocossus, Pediococcus i Lactobacillus. Na rast BMK u vinu i njihov metabolizam utječu razni fizikalno-kemijski čimbenici, poput pH, temperature, koncentracije sumpor(IV)- oksid i etanola. Kompleksne i raznovrsne metaboličke aktivnosti BMK tijekom JMF mogu na kakvoću vina utjecati pozitivno (smanjenje kiselosti, modifikacija mirisa i okusa, mikrobiološka stabilnost) ili negativno (promjene mirisa, boje i tvorba amina)., Malolactic fermentation (MLF) is the biological process of wine deacidification where dicarboxylic L-malic acid is converted to monocarboxylic L-lactic acid and carbon (IV)-oxide. MLF is carried out by lactic acid bacteria (LAB) belonging to three genera: Oenocossus, Pediococcus and Lactobacillus. The growth of LAB and their metabolism in wine is affected by various physico-chemical factors such as pH, temperature, concentration of sulfur (IV)-oxide and ethanol. Complex and diverse metabolic activity of LAB during the MLF can affect the wine quality positively (reduced acidity, aroma and taste modification, microbiological stability) or negatively (changes in odor, color and formation of amines).

Nestabilnosti vina pridonose dušične tvari, proteini, polifenoli, mikroflora, soli kiselina i drugo. Cilj je stabilizacije spriječiti mutnoću i taloženje pojedinih sastojaka vina. Postupci stabilizacije vina su bistrenje, taloženje, sumporenje i filtracija. Filtracijom se iz vina uklanjaju grube i fine čestice mutnoće tako da se vino propušta bilo kroz filtrirajući sloj, ploče ili membrane. Filtracija može biti mehanička i membranska. Pri membranskoj filtraciji na membrani zaostaju molekule i ioni. Membranski su procesi mikrofiltracija, ultrafiltracija, nanofiltracija i reverzna osmoza. Međusobno se razlikuju po mehanizmu i principu separacije, a zajednička im je membrana među dvjema fazama. Za filtraciju vina koristi se membranska mikrofiltracija. Tri su značajna faktora koja utječu na kapacitet: otpor koji pruža materijal od kojeg je načinjena membrana, otpor zbog začepljenja pora membrane te otpor taloga koji se prilikom procesa filtracije stvara na površini membrane. Kada ukupni otpor dosegne graničnu vrijednost, filtracija se mora zaustaviti, a membrana oprati. U ovom je radu istraživan utjecaj mikrofiltracije na tvari arome i kemijski sastav vina sorte graševina. Za filtraciju primijenjena je “cross-flow” filtracija na filteru Microstar, firme Filtrox s modulom sa šupljim vlaknima, ukupne površine modula 20 m2. Promjeri su kapilare: 1,5 mm unutarnji i 2,5 mm vanjski. Promjer šupljina membrane je 0,2 μm, a struktura membrane je asimetrična, izrađena od polisulfona. Membranska filtracija nije značajno utjecala na promjene kemijskog sastava i tvari arome vina., There are several compounds that influence the instability of wine, such as, nitrogen compounds, proteins, polyphenols, microflora, acid salts etc. The aim of the stabilization is to prevent blurriness and sedimentation of certain ingredients of wine. Processes for wine stabilization are elutriation, sedimentation, sulphuration and filtration. Through the process of filtration large and small particles of sediment are removed from wine, in a way that the wine is being filtrated either through the filtering layer, plate or membranes. Filtration can be mechanical and membrane based. Using the membrain filtration results in molecules and ions being sedimented on the membrane. Membranic processes are micro – filtration, ultra – filtration, nano – filtration and reverse osmosis. They differ in mechanisms and principles of separation, but have in common a membrane between the two stages. Membrane filtration is used for filtration of wine. There are three major factors that influence the capacity: resistance provided by the material of which the membrane is made of, resistance created due to obstruction of the membrane pore, and residue resistance that is being created on the membrane surface during the filtration process. When the ultimate resistance reaches its limitation value, filtration must be stopped, and the membrane has to be washed. The objective of this study was to investigate the influence of microfiltration at the aroma substances and the chemical composition of wine sort Graševina has been explored. Cross-flow filtration has been used for filtration on Microstar filter, Filtrox firm, with hollow fibre modul of total proportion of 20 m2. The diameters of the capillary amount to 1,5 mm internal and 2,5 mm external. The diameter of the membrane cavities amounts to 0,2 μm, and the membrane structure is asymmetrical, made from polysulphone. Membrane filtration was not significantly affected chemical composition of wine and aroma substances.