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Sastav vina predmet je brojnih istraživanja, ponajviše zbog utjecaja fenolnih i aromatskih spojeva na senzorna svojstva vina čiju je koncentraciju moguće znatno modificirati primjenom različitih vinifikacijskih tehnologija. Međutim, uz utjecaj na kvalitativna svojstva vina, a s obzirom na suvremene trendove istraživanja vina koja se temelje na proučavanju bioaktivnih spojeva koji blagotvorno djeluju na ljudsko zdravlje cilj ovog istraživanja bio je i pridonijeti spoznaji o vrijednosti autohtone sorte ‘Teran’ koja je nedovoljno istražena u tom smislu. S obzirom da su bioaktivni spojevi često prisutni u vrlo niskim koncentracijama, pojavio se interes za pronalaskom tehnologija koje će povećati njihovu ekstrakciju, ali u isto vrijeme i pozitivno utjecati na aromatski profil vina te očuvati ili čak poboljšati ključne parametre senzorne kvalitete vina. Stoga je glavni cilj ovog istraživanja bio ispitati utjecaj različitih vinifikacijskih tehnologija na kemijski sastav, senzorna svojstva vina i koncentraciju bioaktivnih spojeva u vinima sorte ‘Teran’ (Vitis vinifera L.) kroz identifikaciju i kvantifikaciju fenolnih spojeva, hlapljivih spojeva arome, vitamina C i vitamina B skupine, minerala (makro- i mikroelemenata) te kroz određivanje antioksidacijskog potencijala i senzornih svojstava vina. Pokus je obuhvaćao sljedeće tretmane: kontrola - maceracija u trajanju od 7 dana - TM7 (S), produljena maceracija u trajanju od 10 dana - TM10 (S), produljena postfermentacijska maceracija u trajanju od 21 dan - TM21 (S) te predfermentacijski tretman zagrijavanja u trajanju od 48 sati na 45 °C nakon čega je uslijedila maceracija u ukupnom trajanju od 10 dana - TPHT (S). Istraživan je i utjecaj dozrijevanja vina svih prethodno navedenih tretmana u drvenim hrastovim bačvama u trajanju od šest mjeseci TM7 (Z), TM10 (Z), TM21 (Z), TPHT (Z). Osnovne fizikalno-kemijske analize provedene su prema standardnim metodama O.I.V.-a. Pojedinačni fenolni spojevi analizirani su tekućinskom kromatografijom visoke djelotvornosti (HPLC). Ukupni fenoli te ukupni i slobodni antocijani određeni su spektrofotometrijski. Antioksidacijska aktivnost određena je spektrofotometrijski pomoću FRAP i ORAC testova. Vitamin C i vitamini B skupine analizirani su tekućinskom kromatografijom visoke djelotvornosti. Multielementarnom metodom određivanja elemenata (ICP-OES) određena je koncentracija makro- i mikroelemenata. Hlapljivi spojevi arome izolirani su iz uzoraka vina mikroekstrakcijom na čvrstoj fazi pomoću SPME vlakna, a za određivanje je korištena metoda plinske kromatografije (GC-MS). Uzorci vina ocijenjeni su O.I.V. metodom od 100 bodova te kvantitativnom deskriptivnom senzornom analizom. Rezultati ovog istraživanja pokazali su da su predfermentacijski tretman zagrijavanja masulja - TPHT (S) i produljena postfermentacijska maceracija - TM21 (S) značajno utjecali na povećanje koncentracije hidroksibenzojevih kiselina i ukupnih fenola te vrijednosti antioksidacijskog kapaciteta. Tretman TPHT (S) utjecao je i na porast koncentracija hidroksicimetnih kiselina i mikroelemenata dok je tretman TM21 (S) u vinu ‘Teran’ povećao sadržaj flavan-3-ola, stilbena, slobodnih i ukupnih antocijana, vitamina B kompleksa i makroelemenata. Vina navedenih tretmana ocijenjena su višim ocjenama za senzornu kvalitetu vina, svrstana su u kategoriju vrhunskih vina i opisana višim intenzitetima pozitivnih senzornih svojstava. Dozrijevanje vina je značajno utjecalo na povećanje koncentracije slobodnih hlapljivih spojeva arome, dok su bioaktivni spojevi bili manje stabilni te su se koncentracije dozrijevanjem većinom smanjivale. Tretman dozrijevanja vina značajno je utjecao na senzornu kakvoću vina te su sva vina nakon dozrijevanja bila okusno punija s manje izraženom kiselosti, astringencijom i gorčinom. Dobiveni rezultati ovog istraživanja pridonijeli su definiranju utjecaja predfermentacijskoga zagrijavanja i duljine maceracije masulja te dozrijevanja vina na kemijski sastav, senzorna svojstva i koncentraciju bioaktivnih spojeva u vinima sorte ‘Teran’, a sve s ciljem identifikacije ključnih čimbenika relevantnih u proizvodnji visokokvalitetnih vina te razvoju vinifikacijskih tehnologija koje će maksimalno iskoristiti potencijal sorte. The composition of wine is the subject of numerous studies, mainly due to how phenolic and aromatic compounds influence the sensory properties of wine, where the wine concentration can be significantly modified by applying different vinification technologies. However, in addition to influencing the qualitative properties of wine and considering the contemporary trends in wine research, which are based on the study of bioactive compounds that have a beneficial effect on human health, this research also intended to provide additional knowledge about the value of the ‘Teran’ autochthonous variety, which has been insufficiently researched. Different groups of bioactive compounds were detected in wine, including phenolic compounds, vitamin C, B complex vitamins and minerals. Phenolic compounds are the most abundant bioactive compounds in wine, and numerous studies provide evidence of the pharmacological, biological, and physiological benefits for human health, including blood pressure, cholesterol and lipids regulation, prevention of diabetes, obesity, atherosclerosis and cardiovascular diseases, as well as anti-inflammatory, antioxidant and antitumor effects. Macro- and microelements play an essential role in the human body, such as building strong bones and transmitting nerve impulses, and are also able to participate in the biosynthesis of different hormones, regulate normal heartbeat, effective in controlling blood pressure, and are involved in immune and brain systems. Wine also includes vitamins, among the nutrients required for the many physiological functions essential to life. Besides nutritional health benefits, a close relationship exists between high-quality wines and high phenolic content, given that phenolic compounds increase the sensory characteristics of wines in terms of color, astringency, and bitterness. Whether positively or negatively, macro- and microelements play an important role in the organoleptic characteristics of wines. Some of them are necessary for the fermentation process and can directly or indirectly impact the clarity and sensory properties of wines, including flavor, freshness, aroma, color, and taste. Certain vitamins are known to affect the formation of aroma compounds. Given that bioactive compounds are often present in very low concentrations, there has been an interest in finding technologies that will increase the extraction of such compounds but, at the same time, have a positive effect on the aromatic profile of wines and preserve or even improve the key parameters of the sensory quality of the wine. Therefore, the main goal of this research was to examine the impact of different vinification technologies on the chemical composition, sensory properties of wine and the concentration of bioactive compounds in wines of the ‘Teran’ variety (Vitis vinifera L.) through to identification and quantification of phenolic compounds, volatile aroma compounds, vitamin C and vitamins of the B group, minerals (macro and microelements) and determination of the antioxidant potential and sensory properties of wine. The experiment was performed in 2018 and 2019 with a grape variety called ‘Teran’, an autochthonous red grapevine variety grown for centuries in the north Adriatic regions of Croatia, Slovenia and Italy. Different vinification processes were carried out: control treatment with 7 days of maceration - TM7 (S), prolonged 10-day maceration - TM10 (S), prolonged post-fermentative 21-day maceration - TM21 (S), where fermentation of all the three treatments was conducted at 24 °C, and 48-hour pre-fermentative maceration heating at 45 °C followed by eight-day classical maceration - TPHT (S) (10 days of maceration in total). Accordingly, all the wine samples were aged in oak barrels for six months, TM7 (Z), TM10 (Z), TM21 (Z) and TPHT (Z). Treatments were done in three replications. The basic physicochemical parameters were analyzed according to methods set by the International Organization of Vine and Wine. The separation of individual phenols (hydroxycinnamic and hydroxybenzoic acids, flavan-3-ols and stilbenes) was carried out by high-performance liquid chromatography (HPLC). Total phenolic content, free and total anthocyanins and determination of antioxidant capacity by FRAP and ORAC assays were performed on a spectrophotometer. The determination of macro- and microelements was conducted using an inductively coupled plasma optical emission spectrometer (ICP-OES). Vitamin C and vitamins of the B group were analyzed using HPLC. Volatile aroma compounds were isolated using headspace-solid phase microextraction (HS-SPME), and analyzed using gas chromatography/mass spectrometry (GC/MS). Sensory analysis was based on two evaluation methods: quantitative descriptive analysis (QDA) and the 100-point O.I.V./U.I.O.E. evaluation method. One-way analysis of variance (ANOVA) and Fisher’s least significant difference (LSD) test were used to compare the means (n = 3) at the level of significance of p < 0.05. The data were subjected to unsupervised statistical analysis using PCA to visualize the relationship between the Teran wines obtained from different treatments and bioactive compounds. Based on the results of the two-year research, the conclusion is that the treatment of pre-fermentation mash heating - TPHT (S) and the treatment of prolonged post-fermentation maceration - TM21 (S) in the Teran wine significantly increased the concentrations of hydroxybenzoic acids, total phenols and the values of antioxidant capacity. In addition, the treatment of pre-fermentation mash heating - TPHT (S) influenced the increase in the concentration of hydroxycinnamic acids and microelements, while the treatment of prolonged post-fermentation maceration - TM21 (S) in the Teran wine increased the content of flavan-3-ol, stilbene, free and total anthocyanin, vitamin B complex and macroelements. TPHT (S) treatment and TM21 (S) treatment reduced the concentration of almost all groups of free volatile compounds compared to the control treatment. However, despite the reduction in the concentration of free volatile compounds, the wines of the mentioned treatments were evaluated with higher scores for the sensory quality of the wine. They were classified in the category of premium wines and described with higher intensities of positive sensory properties, among which dry/dried fruit and spicy/aromatic herbs, while the fullness of the body, the presence of tannins and the aftertaste stand out among the taste properties. In the olfactory properties, the treatment TM21 (S) additionally stood out for its accentuated fruitiness and viscosity, and sweetness of taste, while the intensity of bitterness and astringency was not overemphasized despite the significantly higher concentration of phenolic compounds, especially flavan-3-ol.The application of prolonged maceration treatment for 10 days - TM10 (S), as well as the application of maceration for seven days, which was the control treatment - TM7 (S), did not significantly affect the increase in the concentration of bioactive wine compounds. However, the mentioned treatments resulted in significantly higher concentrations of almost all groups of free volatile aroma compounds compared to the remaining two treatments. Despite the increase mentioned above in the concentration of free volatile aroma compounds, the mentioned treatments were characterized by a lower intensity of almost all olfactory properties and emphasized freshness, acidity, astringency, and bitterness. Maturation of wine in oak barrels for six months had a significant impact on increasing the concentration of free volatile aroma compounds, especially from the group C-13 norisoprenoids, volatile phenols, furans and lactones. Other compounds, especially bioactive compounds such as vitamins of the B group, macroelements, and microelements, as well as most phenolic compounds, were less stable, and their concentrations mostly decreased with maturation. The wine maturation treatment significantly influenced the sensory quality of the wine, and fruity aromas characterized the wines of all treatments after maturation, while the TM21 (Z) and TPHT (Z) treatments stood out with more pronounced aromas of dried and dried fruit, jam, and liqueur. After maturation, all wines had a fuller taste with less pronounced acidity, astringency, and bitterness. The obtained results of this research contributed to the definition of the influence of pre-fermentation heating and length of maceration and wine maturation on the chemical composition, sensory properties, and concentration of bioactive compounds in wines of the ‘Teran’ variety, all due to the identification of key factors relevant in the production of high-quality wines and the development of vinification technologies which maximize the potential of the variety.

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.

Algae and cyanobacteria, other than their nutritional value, possess different beneficial properties, including antioxidant and antimicrobial ones. Therefore, they can be considered functional ingredients in animal feed and natural substitutes for antibiotics. The aim of this study was to evaluate the antioxidant and antimicrobial capacity against porcine O138 E. coli of Ascophyllum nodosum, Chlorella vulgaris, Lithotamnium calcareum, Schizochytrium spp. as algal species and Arthrospira platensis as cyanobacteria. The antioxidant capacity was determined by ABTS Radical Cation Decolorization Assay testing at three different concentrations (100%; 75%; 50%). The growth inhibition effect of the extracts at concentrations of 25%, 12.5%, 6%, 3% and 1.5% against porcine O138 E. coli was genetically characterized by PCR to detect the presence of major virulence factors; this was evaluated by following the microdilution bacterial growth method. The ABTS assay disclosed that Ascophyllum nodosum was the compound with the major antioxidant properties (57.75 ± 1.44 percentage of inhibition; p < 0.0001). All the extracts tested showed growth inhibition activity at a concentration of 25%. Among all extracts, A. nodosum was the most effective, showing a significant growth inhibition of E. coli; in particular, the log10 cells/mL of E. coli used as a control resulted in a significantly higher concentration of 25% and 12.5% after 4 h (8.45 ± 0.036 and 7.22 ± 0.025 log10 cells/mL, respectively; p < 0.005). This also suggests a dose-dependent relationship between the inhibitory activity and the concentration. Also, a synergistic effect was observed on antioxidant activity for the combination of Ascophyllum nodosum and Lithotamnium calcareum (p < 0.0001). Moreover, to determine if this combination could affect the viability of the IPEC-J2 cells under the normal or stress condition, the viability and membrane integrity were tested, disclosing that the combination mitigated the oxidative stress experimentally induced by increasing the cell viability. In conclusion, the results obtained highlight that the bioactive compounds of algal species are able to exert antioxidant capacity and modulate O138 E. coli growth. Also, the combination of Ascophyllum nodosum and Lithotamnium calcareum species can enhance their bioactivity, making them a promising functional feed additive and a suitable alternative to antibiotics.

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.

Since the discovery of the so-called ‘French paradox’ by Renaud & de Lorgeril, M. (1992), a diet of high fat and cholesterol intake along with red wine that does not negatively impact health, such as cardiovascular risks, medical surveys found more positive relations of wine and health and more biochemical substances with positive effects on human health (Anekonda 2016 ; Golderg . The positive effects include blood pressure, cholesterol levels, blood lipids, diabetes, obesity regulation, prevention of atherosclerosis, cardiovascular disease, anti-inflammatory and antitumor effects. In addition to the positive impact on physical health, evidence exist on positive impacts of phenolic compounds (stilbenes, especially resveratrol) on mental health regarding protecting neuronal cells from damage, preventing the development of neurodegenerative diseases, treating depression, improving cognitive function, and increasing memory (Ares et al., 2015 ; Diener et al., 1999 ; Guilemin et al., 2016). The positive psychological responses of humans caused by moderate wine consumption respond to a positive sense psychological well-being, fewer or no symptoms of depression, and a higher level of positive affects and lower negative affects. During the scientific project “Vinum Sanum” several research questions were set and hypothesis upon whom surveys were conducted. The surveys included questions about human behaviour towards wine, medical aspects of wine consumption, comparison of consumers and non-consumers perceptions about health attributes of wine. The study was carried out in accordance with the Declaration of Helsinki developed by the World Medical Association and was approved by the Ethics Committee of the Clinical Hospital Center Rijeka (Croatia).The purpose of the study presented in this article was to show how wine consumers perceive wine and how it affects their psychological state. The main objective of this survey was to provide evidence about moderate wine consumption of Malvazija istarska on human health, the possible positive effects of wine consumption on psychological well-being and to detect positive perceptions towards wine. The objective was achieved by testing participants during a period of six weeks of moderate wine consumption of autochthonous Croatian grapevine variety Malvazija istarska (Vitis vinifera L.) produced in Istria county. The data were collected from wine consumers at two time points (in June and July 2019) before and after wine consumption with a self-completed questionnaire that was administered by trained researchers. Two questionnaires were used, one to measure the psychological response of the influence of moderate wine consumption and one to measure the perception of wine and its health attributes. Variables were measured with the Likert scale (1-5 for wine attributes and 1-10 for psychological affects). For data processing descriptive analysis (M, SD), and factor analysis were used. Results indicate the awareness of positive health aspects of wine consumption, connected to the positive effects of wine on cardiovascular health (namely, heart, blood vessels health and levels of blood cholesterol). Wine was perceived as a natural and healthy beverage, in a positive sense with its relaxation, hedonistic effects and quality attributes (ageing/vintage, terroir, micro region/vineyards). The psychological affects/subjective well-being included negative stress affects (being nervous, anxious and under pressure) that were explained by everyday pressures of work and family obligations. The construct of negative affects was separate from the positive affects expressed with feelings of happiness, emotional stability and positive general well-being feelings. The obtained results about positive effects of moderate wine consumption may be useful for other researchers in medical branches who question if moderate wine consumption has positive of negative effects on human health, and may serve in current discussions at the World Health Organization on wine and health.

Phenolic acids and stilbenes are important groups of non-flavonoid phenolic compounds present in grapes and wine. Their content in wine may be modulated by the vinification technique applied. The present study aimed to determine the impact of the application of different grape mash maceration treatments on the composition of hydroxycinnamic (HCA) and hydroxybenzoic acids (HBA) and stilbenes in Malvazija istarska wines. The research was conducted at the Institute of Agriculture and Tourism (Poreč, Croatia) with Malvazija istarska (Vitis vinifera L.), an autochthonous Croatian white grape variety. A total of six vinification treatments were carried out: two days maceration treatment at 8 °C (CRYO), and seven (M7), 14 (M14), 21 (M21), and 42 days (M42) maceration treatments at 16 °C, compared with the control treatment without maceration (C). Identification and quantification of phenolic acids and stilbenes was performed after direct injection of the filtered wine sample, using a high performance liquid chromatograph (HPLC) equipped with a diode array detector (DAD). The obtained results were statistically processed by one-way analysis of variance (ANOVA) and Fisher's test of least significant differences (LSD). According to the obtained results, the highest concentration of total HBAs was recorded in prolonged post-fermentative maceration treatment M42, and among all HBAs gallic acid had significantly the highest concentrations. Regarding HCAs, the total content was significantly the highest in seven days maceration treatment (M7), while in longer maceration treatments (M14, M21, M42) total HCA content 58 gradually decreased as maceration progressed. When observing individual HCAs, transcaftaric acid had the highest concentrations, especially in M7 treatment wine, while caffeic and ferulic acids reached the highest concentrations in pre-fermentative two days (CRYO) treatment. Regarding total stilbene content, treatments M7, M14, and M21 obtained the highest concentrations, but did not significantly differ between each other, and when observing individual stilbenes, cis-piceid concentrations were the highest in those treatments and among all identified stilbenes. Obtained results show that HBA content benefits from the prolonged maceration, while for the most HCAs and stilbenes concentrations increase up to seven days of maceration and then decrease during prolonged maceration, possibly due to oxidation and other reactions.

Moderate wine consumption may impact several human health aspects, among other as a result of phenolic compounds present in wine and their bioactive properties. The aim of this study was to determine whether six weeks of daily, moderate Teran red wine consumption affects the levels of total cholesterol, high-density lipoprotein cholesterol – HDL, low-density lipoprotein cholesterol – LDL, and triglycerides. Sixty-eight healthy adults (46 women and 22 men) aged 25-64 years voluntarily agreed to participate in the study. The study was carried out in accordance with the Declaration of Helsinki developed by the World Medical Association and was approved by the Ethics Committee of the Clinical Hospital Center Rijeka (Croatia). Informed consent was obtained from all subjects involved in the study. Participants were divided into two groups, consumers (49 participants) and non-consumers (19 participants). Non-consumers were asked to avoid any alcohol intake during the six study weeks, while consumers were asked to consume one glass of red wine (200 mL) per day and not to drink any extra alcohol. Blood samples for laboratory tests were drawn just before the start and at the end of the study period. Total cholesterol, HDL, LDL, and triglycerides were analyzed on biochemistry analyzer at Clinical Hospital Centre Rijeka, using standard laboratory methods. Total phenols in wine expressed as gallic acid equivalents in mg/L of wine (mg GAE/L) were determined by the Folin- Ciocalteu colorimetric method using a UV/Vis spectrophotometer. One-way analysis of variance and Fischer’s least significant difference test at the level of significance p ≤ 0.05 were used to compare the groups of participants. The differences between the values obtained in the second (the end of the study period) and the first measurement (before the start of the study period) of their blood parameters were used in statistical analysis. The consumed red wine was produced at the Institute of Agriculture and Tourism (Poreč, Croatia) from an old autochthonous grapevine variety Teran (Vitis vinifera L.). The total phenolic content in the produced wines ranged from 2369 mg to 2917 mg GAE/L. No significant differences were observed between the consumers and non-consumers regarding blood lipid profile. However, considering that alcohol consumption generally can negatively affect cholesterol levels, our findings suggest that the beneficial effects of phenolics and/or other wine constituents possibly overcame the negative alcohol effects on health. Although it does not provide any evidence of significant positive or negative effect of moderate Teran red wine consumption on blood lipid profile, this study could suggest that daily moderate wine consumption can be considered as a component of the healthy lifestyle regarding the investigated parameters.

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.

The rising trend of moderate wine consumption as a part of a healthy lifestyle promotes white wines with higher phenolic content because of their bioactive properties. Duration and temperature of the maceration process have a marked impact on the content and composition of wine phenolics. The aim of this study was to explore the effect of applying maceration processes of different durations and temperature on total phenolic content and flavan-3-ol compounds concentration of Malvazija istarska (Vitis vinifera L.) wines, an autochthonous Croatian white grape variety. Vinification took place at the Institute of Agriculture and Tourism (Poreč) where pre-fermentative two days cryomaceration treatment at 8 °C (CRYO), seven days maceration treatment at 16 °C (M7), and prolonged post- fermentative maceration treatments at 16 °C for 14 days (M14), 21 day (M21), and 42 days (M42) were studied and compared to non- maceration control treatment (C). Total phenolic content was determined by the Folin-Ciocalteu colorimetric method using a UV/VIS spectrophotometer and the results were expressed as gallic acid equivalents (mg/L GAE). The analysis of flavan-3-ols was carried out by high performance liquid chromatography (HPLC). Identification was performed by comparing retention times and spectra with those of pure standards. Procyanidins B1, B2, B3, C1, and (+)-catechin and (-)-epicatechin were identified in all wine samples. Statistical data analysis was performed using one-way analysis of variance (ANOVA) and Fischer’s least significant difference (LSD), while Pearson’s correlation was used to observe the relationship between total phenolic content and total flavan-3-ols. According to the obtained results, total phenolic content increased in all maceration treatments when compared to C treatment wine. The increase in total phenolic content was the highest in post- fermentative maceration treatments, M14 and M42. Total flavan-3-ol content showed a similar trend, also reaching the highest values in M14 and M42 treatment wines, while the lowest concentrations were observed in both C and CRYO treatments. A high positive correlation was observed between total phenolic content and total flavan-3-ols. When observing individual flavan-3-ol compounds, (-)-epicatechin reached the highest concentrations, especially in M42 treatment. Procyanidin B3 and C1 significantly increased only when 42 days maceration was applied, while shorter maceration durations or temperature did not affect the increase in these compounds. It can be concluded that the investigated phenolics highly depended on the maceration conditions applied. Additionally, the increase levels of bioactive phenols resulting from the application of the investigated maceration practices might attract those consumers interested in moderate white wine consumption for specific health reasons. The study was funded by the Croatian Scientific Foundation under the projects IP 2018-5049 and DOK-2020-01-1901.

Wine is a rich source of various nutritive bioactive compounds, including macro- and microelements. A moderate wine consumption of 250-300 ml/day contributes to the requirements of the human organism for essential elements. Current studies attribute the consumption of foods rich in nutrients even as potential inhibitors of SARS-CoV-2. Moreover, supplementation of micronutrients may positively impact the recovery from COVID-19 infection. However, some metals can be potentially toxic when consumed in excess, and the maximum acceptable levels in wine have been established. The aim of this study was to determine the effects of vinification techniques on mineral composition and estimate the changes in composition during the barrel aging. The experiment was performed in vintage 2019, with grapes from Teran (Vitis vinifera L.) variety. Vinification took place in the experimental wine cellar of the Institute of Agriculture and Tourism in Poreč (Croatia). 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 (TM7-B, TM10-B, TM21-B, TPHT-B). The determination of eight elements was conducted by Optima DV 2000 inductively coupled plasma-optical emission spectrometer. Analysed elements were identified by ICP-OES and were quantified by the direct calibration method. Statistical data analysis was performed using one-way analysis of variance (ANOVA) and Fischer’s least significant difference (LSD) to compare the means (n = 3) at the level of significance of p ≤ 0.05. In the investigated wines, K, Ca, Mg, and Na were identified as macroelements, and Al, Cu, Fe, and Mn as microelements. Results in this study showed the significant impact of different treatments on mineral composition. More precisely, compared to control (TM7), TM10, and TM21 treatments showed significantly higher concentrations of total macroelements, while TPHT treatment showed significantly lower concentrations. The significantly highest concentration of macroelements in aged wines was found in TM21-B wines. It is important to note that wine barrel aging significantly reduced the level of all investigated macroelements except Mg, which remained stable in all treatments. The content of total microelements in young wines was significantly the highest in pre-fermentative heating treatment. The same trend continued in aged wines, with the highest concentration in TPHT-B treatment. It should be pointed that the concentration of all investigated microelements was significantly reduced during barrel aging. This result indicates that some interesting differences can be obtained among wines by applying maceration, heating, and barrel aging in the composition of macro- and microelements. In addition, since metals can form organometallic complexes with anthocyanins and tannins and cause the formation of precipitates, it was very interesting to monitor the evolution of wines during maturation and aging. Obtained results can probably be attributed to the different extraction mechanisms/kinetics from solid parts of grapes, particularly the skin, which was shown to be the most important fraction in terms of metal concentration. Regarding aging, earlier studies indicated, that metal composition is not stable, which was also confirmed in this research. However, the intensity of these changes can vary depending on grape and wine composition. This study was funded by the Croatian Science Foundation under the projects VINUM SANUM (IP 2018-5049) and DOK-2018-09.

This study aimed to determine total phenolic content and concentrations of individual phenolics in cold-pressed grape seed oil obtained by screw pressing of grape seeds of cv. Teran (Vitis vinifera L.). Those seeds derived from six different vinification treatments that were submitted: to 48-h pre- fermentative mash cooling (8 °C) followed by maceration of 13 days (C15), 28 days (C30) and saignée technique followed by maceration of 13 days (CS15), and to 48-h pre- fermentative heating (50 °C) followed by maceration of 13 days (H15) and 28 days (H30). Also, this experiment included a control tank (K7), with a 7- day maceration. After macerations ended, fermented mashes were pressed, and seeds were collected and dried at 38 °C in dehydrating chamber until 5-8 % of moisture content in seeds was reached. Then they were vacuum-packed and stored until screw pressing. The obtained oil was centrifuged and stored at -18 °C prior to analysis. Total phenolic content (TPC) was analyzed by Folin–Ciocalteau colorimetric method and UV/VIS spectrophotometer. Individual phenolic compounds were analyzed by high-performance liquid chromatography (HPLC). Results showed that total phenolic content (mgCAEkg-1 oil) in oil from all treatments, except C15, was significantly higher compared to oil from the control treatment (K7). Respectively, TPC increased with longer duration of maceration. Regarding individual phenolics, it was found that resveratrol, tyrosol, quercetin and kaempferol were significantly the highest in oil from pre-fermentative heating treatment (H30). Obtained results suggested a noticeable impact of pre fermentative treatments and prolonged macerations on phenolics in cold-pressed grape seed oil.