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Prirodno pjenušavo ružičasto vino od autohtonog kultivara vinove loze Teran (Vitis vinifera L.) proizvedeno je metodom vrenja u boci uz primjenu inkapsuliranog kvasca ProElif® (Saccharomyces cerevisiae) i komercijalnog suhog kvasca Fermol Blanc (Saccharomyces bayanus). Tijekom istraživanja uspoređivana je aktivnost korištenih kvasaca s obzirom na brzinu razgradnje šećera tijekom fermentacije u boci te njihov utjecaj na osnovna fizikalno kemijska svojstva i fenolni profil gotovog pjenušavog vina te parametre pjene i iskrenja. Brža razgradnja šećera, kao i veći udio pojedinačnih i ukupnih fenolnih spojeva utvrđen je u pjenušavim vinima proizvedenim primjenom inkapsuliranog kvasca ProElif®. S druge strane, vina proizvedena kvascem Fermol Blanc odlikovala su se višim suhim ekstraktom te većom kvalitetom pjene i iskrenja. Uočene senzorske razlike u vinima nisu imale negativnih implikacija pri definiranju njihove sveobuhvatne kakvoće, The influence of encapsulated yeast ProElif® (Saccharomyces cerevisiae) in comparison with the yeast Fermol Blanc (Saccharomyces bayanus) in the production of naturally sparkling rosé wine by bottle fermentation produced from the indigenous grape cultivar Teran (Vitis vinifera L.) was investigated. During the research, the following were monitored: the length of sugar decomposition during fermentation in the bottle, and in the finalized sparkling wines, physicochemical parameters, foam and sparkling parameters and phenolic profile. Faster breakdown of sugars, as well as a higher proportion of individual and total phenolic compounds have been recorded in wines with ProElif® yeast. On the other hand, wines produced with Fermol Blanc yeast were characterized by a higher dry extract and higher quality of foam and sparkling. Sensory differences were observed in wines without negative implications for their final quality.

Six vinification treatments, including control treatment (K7) were carried out to investigate: the impact of 48-h pre-fermentative mash cooling (8 °C) followed by 13-days maceration (C15), 28- days maceration (C30) and saignée technique (CS15) ; and the impact of 48-h heating (50 °C) followed by 13-days maceration (H15) and 28 days (H30) on total phenolic content (TPC) and antioxidant capacity (AC) in Teran wines. TPC was analysed by a method based on Folin–Ciocalteu reagent and AC was determined by FRAP and ORAC assay. The results showed higher TPC and AC in all treatments compared to the control wine (K7). The highest TPC was found after saignée technique applied (CS15). Pre-fermentative heating and 30-day maceration treatment (H30) showed the strongest antioxidant capacity, with both FRAP and ORAC assay.

This study aimed to determine antioxidant capacity and total phenolic content in red wine obtained from cv. Teran (Vitis vinifera L.), autochtonous Croatian grape variety. Five different vinification treatments were submitted to: 48-hour pre-fermentative mash cooling (8 °C) followed by prolonged post-fermentative maceration of 13 days (C15), 28 days (C30), and saignée technique (juice runoff) proceeded with maceration of 13 days (CS15) ; and to 48-hour heating (50 °C) followed by maceration of 13 days (H15) and 28 days (H30). Also, this experiment included a control treatment (K7), with a standard 7-day maceration. The antioxidant capacity of the wines was determined by the ferric reducing/antioxidant power (FRAP) assay and the oxygen radical absorbance capacity (ORAC) assay. Fluorescence was measured by spectrofluorometer. The FRAP assay results are expressed in mmol/L FeSO4 × 7H2O, and the ORAC assay results are expressed as mmol/L of Trolox equivalents (TE). Total phenolic content (TPC) was determined by the Folin–Ciocalteu colorimetric method using a UV/Vis spectrophotometer. The results are expressed as gallic acid equivalents in mg/L of wine (mg GAE/L). Obtained results showed that both FRAP and ORAC assay values in all treatments were significantly higher compared to the control treatment (K7). Also, the two assays showed a strong correlation (r= 0.998). FRAP assay values ranged from 10.77 to 23.67 mM Fe2+, and ORAC assay values ranged from 17.77 to 31.67 mM Trolox. The highest values of both assays were obtained in treatment submitted to pre-fermentative heating and 30-day maceration (H30). Total phenolic content varied from 821.52 mg GAE/L in control wine (K7) to significantly the highest value, 2710.61 mg GAE/L in treatment where saignée technique and 15-day maceration were performed (CS15). In comparison to control wine (K7) TPC in all treatments was statistically higher. Obtained results suggested a noticeable impact of saignée technique and 15-day maceration on TPC, and the impact of pre-fermentative mash heating and 30-day maceration on antioxidant capacity. According to our results, Teran red wine, affected by particular vinification processes considered a strong source of bioactive compounds, as well their beneficial properties can contribute to human health.

To investigate the effect of different maceration techniques on the mineral composition of Malvazija istarska wines, five different maceration treatments were carried out. Maceration techniques of two days at 8 °C (CRYO), and seven (M7), 14 (M14), 21 (M21), and 42 days (M42) at 16 °C, were studied and compared to control treatment without maceration (C). Analysis of macro- and microelements was conducted by inductively coupled plasma- optical emission spectrometry (ICP-OES). According to the obtained results, the longest maceration treatments (M21 and M42) resulted with the highest concentration of almost all macroelements. A proportional increase with maceration time was observed in the concentration of all analyzed microelements, with M42 treatment wine resulting in significantly highest concentrations.

The objective of this study was to determine the effects of four winemaking techniques on water- soluble vitamin content and estimate the changes in their range during the barrel aging of Teran red wines. The study covered seven days of maceration as a control treatment (TM7), prolonged 10-day maceration (TM10), prolonged post- fermentative 21-day maceration (TM21), and 48-h pre-fermentative maceration heat treatment at 45 °C followed by eight-day standard maceration (TPHT). The fermentation of all treatments was conducted at 24 °C. Accordingly, all the wine samples were aged in oak barrels for six months. Vitamins were analyzed using high-performance liquid chromatography with UV-Vis diode array and single quadrupole mass detector equipped with electrospray ionization interface. The thiamine (vitamin B1), riboflavin (vitamin B2), niacin (vitamin B3), pyridoxine (vitamin B6), and ascorbic acid (vitamin C) were determined. Total B complex vitamin content of young Teran wines significantly increased with prolonged skin contact. Furthermore, the results showed that significantly the highest content of total B- complex vitamins was detected in TM21 wine, followed by TM10 treatment. Regarding the vitamin C concentration in young Teran wines, there were no statistical differences between TM7, TM10, TM21 treatments, while TPHT treatment showed a significantly lower concentration. Wine barrel aging significantly reduced the level of all investigated vitamins except vitamin B6, which remained stable in all treatments. This study showed that winemaking techniques could affect the vitamin concentrations in wine.

Six vinification treatments, including control wine (TK7) were carried out to investigate: the impact of 48-h pre-fermentative mash cooling (8 °C) followed by maceration of 13 days (TC15), 28 days (TC30) and saignée technique (TCS15) ; and the impact of 48-h heating (50 °C) followed by maceration of 13 days (TH15) and 28 days (TH30) on anthocyanin concentration and color in Teran wines. Anthocyanins, intensity, hue and composition of color were analyzed by UV/Vis spectrometry. The results showed that total anthocyanins and color hue values in all treatments were higher compared to control wine. The highest concentrations of free anthocyanins were found in wines with pre-fermentative heating treatment. Color intensity exposed the best results in 15-day macerations regardless of pre- fermentative treatment.

The aim of this study was to establish the relationship between some sensory attributes and the overall impression of native Croatian red wine variety Teran (Vitis vinifera L.). Wines were produced with four different vinification techniques: control (7-days maceration, TM7), prolonged maceration 10 and 21 days (TM10, TM21 respectively), and pre- fermentation heating treatment (TPHT). The sensory profile of wine samples was obtained using quantitative descriptive analysis (QDA) and 100 points O.I.V/U.I.O.E. evaluation method. Five panelists rated the intensity of body/fullness, astringency, viscosity, aftertaste quality, and varietal typicity of taste. The results showed a positive correlation between the intensity of most taste attributes and the overall wine impression. A strong negative correlation was observed for astringency. All observed treatments, highlighting post-fermentative prolonged 21-day maceration and pre-fermentation heating treatment, contributed to the positive effect on taste profile and overall wine impression regarding control treatment.

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 (coinoculation) 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. Coinoculation 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., Jabučno-mliječna fermentacija (JMF) složen je biokemijski proces koji ima važnu ulogu u proizvodnji većine crnih vina. Glavni učinci primjene JMF su snižavanje ukupne kiselosti uz rast pH vrijednosti, mikrobiološka stabilnost vina te promjena aromatskih senzornih svojstava vina. Cilj ovog istraživanja bio je utvrditi utjecaj različitih načina jabučnomliječne fermentacije na kompatibilnost kvasca i bakterija, duljinu trajanja fermentacije, koncentraciju pojedinačnih organskih kiselina i spojeva arome te senzorna svojstva vina sorte ´Teran´ (Vitis vinifera L.). Pokus je obuhvaćao kontrolni tretman (bez JMF), spontanu JMF, induciranu JMF u početku alkoholne fermentacije (koinokulacija) te induciranu JMF po završenoj alkoholnoj fermentaciji. U svim tretmanima alkoholna fermentacija je u potpunosti završila, bez zastoja ili usporavanja. Koinokulacija je utjecala na značajno kraće trajanje JMF. Svi tretmani s JMF značajno su utjecali na sniženje koncentracije titracijske kiselosti i povećanje pH vrijednosti. Najviše koncentracije hlapive kiselosti i etil acetata utvrđene su u vinima spontane JMF. U svim tretmanima s JMF zabilježena je potpuna razgradnja jabučne kiseline te sniženje koncentracije limunske kiseline, ukupnih viših alkohola i acetaldehida. Nadalje, značajno više koncentracije etilnih estera, diacetila, acetoina i 2,3-butandiola zabilježene su u svim tretmanima s JMF.

The aim of this work was to study the influence of different vinification techniques on stilbenes and total polyphenolic content in red wines made from cv. Teran (Vitis vinifera L.). Four different vinification techniques were carried out: control (7 days maceration), prolonged maceration (10 and 21 days), and thermovinification. Four stilbenes were determined by high-performance liquid chromatography (HPLC), and total polyphenols were determined by spectrophotometric methods. The results showed the treatment of extended maceration (21 days) had a significant effect on the increase of total (35.74 mg/L) and individual stilbenes (trans-piceid, cis-piceid, trans-piceatannol, trans-resveratrol), as well as total polyphenols (2702.88 mg GAE/L). Treatment of thermovinification resulted in significant increase of the total polyphenolic content by nearly 20% in relation to control.

Cilj ovog istraživanja bio je utvrditi utjecaj duljine trajanja i temperature maceracije na koncentraciju slobodnih i ukupnih antocijana te parametre boje u vinima sorte ‘Teran’. Provedena su četiri različita vinifikacijska tretmana: 7 dana maceracije (TM7, kontrolni tretman), 10 dana (TM10) i 21 dan maceracije (TM21) pri temperaturi od 24°C, te 10 dana maceracije uz zagrijavanje masulja na 45°C prvih 48 sati (pred-fermentacijsko zagrijavanje masulja, TPHT). Koncentracija ukupnih i slobodnih antocijana, te intenzitet, nijansa i kompozicija boje određeni su spektrofotometrijski. Koncentracija ukupnih antocijana kretala se od 334, 3 mg/L do 444, 73 mg/L (TPHT, TM21), a slobodnih antocijana od 76, 73 mg/L do 113, 57 mg/L (TM10, TM21), tretman produljene maceracije (TM21) imao je značajan utjecaj na povećanje koncentracije ukupnih i slobodnih antocijana. Intenzitet boje kretao se u rasponu od 1, 59 do 1, 69 (TM10, TPHT), a nijansa boje od 0, 52 do 0, 54, pri čemu je kontrolni tretman imao signifikantno najnižu izmjerenu vrijednost nijanse boje. Unatoč nižoj koncentraciji slobodnih i ukupnih antocijana, kod pred-fermentacijskog tretmana zagrijavanja zabilježen je signifikantno najveći intenzitet boje, što je vjerojatno posljedica procesa kopigmentacije, odnosno tvorbe polimernih pigmenata. Iz dobivenih rezultata može se zaključiti da duljina trajanja i temperatura maceracije značajno utječu na sastav vina. Poduljena maceracija vodi ka povećanju koncentracije slobodnih i ukupnih antocijana, dok pred-fermentacijsko zagrijavanje utječe na povećanje intenziteta i stabilnosti boje, stoga oba tretmana mogu imati praktičnu primjenu u proizvodnji crnih vina.

In Croatia is observed the increasing trend in mean annual air temperature and the large variability in the measured extreme precipitation from prominent drought to severe flooding. Climatological studies based on regional climate models show the intensification of the extreme values of temperature and precipitation over Europe in the future climate. These changes in temperature and precipitation have a great impact on viticulture, considering that of all living organisms, plants react first to the change of surface temperature. Due to climate change, changes in temperature will affect: (i) differently all developmental stages of vines in certain wine-growing areas in Croatia (i.e. their phenological characteristics) and (ii) differently on different varieties. At the same time, the temperature increase changes convective activity (storms) and thus the occurrence of hail that are estimated as the second biggest cause of material damage in Croatia. The trend of increasing average duration of hailfall was also observed on the basis of measurements obtained in the low land of Croatia. Due to mentioned, this project has several goals. Based on meteorological and climatological datasets and wine and grapevine archive data, the current situation and a monitoring system of key phenological phases of the vine due to climate change will be analyzed and established. Furthermore, the aim is to link the ripening and quality of grapes with agro-climatic indices and determine the relationship between hail parameters and the degree of damages in grapevines. The purpose is also to enable: (i) detailed agronomic and economic evaluation for preserving Croatian autochthonous grapevine varieties, (ii) determination of climate changes through agro-climatic indices in different future periods and (iii) an estimation of the increase or decrease in certain weather types which favor co nvective developments (and hail).