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This study focuses on the impact of new methods for inhibiting malolactic fermentation in white wines on their analytical and sensory properties. Enological preparations with different mechanisms of effect were tested: fumaric acid, chitosan, Estaan (a preparation based on tannin inhibition), medium-chain fatty acids (MCFAs), sulphur dioxide and a control variant. Malolactic fermentation (MLF) was also performed. The samples underwent analysis through HPLC (high-performance liquid chromatography) to determine the concentrations of malic and lactic acid, as well as biogenic amines. GC (gas chromatography) analysis was used to monitor volatile substances, alongside sensory evaluation. This study demonstrated a significant influence of individual enological preparations on the aromatic profile of the examined wines. The SO2 and MCFA variants exhibited the highest concentrations of volatile substances within the esters group, specifically isoamyl acetate, 1-hexyl acetate and phenylethyl acetate. Conversely, the fumaric acid and Estaan variants displayed the lowest concentrations of these esters. The most notable disparities were observed in acetoin concentration, with the MCFA variant exhibiting the lowest values. Additionally, the chitosan variant showed higher concentrations of putrescine and spermidine compared to the MCFA and fumaric acid variants, which presented the lowest levels.

In this paper we focus on possibilities of using natural microflora from vineyards to enhance spontaneous fermentation. Obtained yeast isolates, naturally occurring in vineyards, which were previously isolated in 2017 and 2018, were used for inoculation of Hibernal grape must. Spontaneously fermented musts and musts with the yeast isolates from 2017 and 2018 were compared. Basic parameters of the musts (sugar concentration, pH, concentration of titratable acids, concentration of assimilated nitrogen) were analysed studied, and a sensory analysis of the resultant wines was performed. The fermentation with the yeast isolates was quick and smooth. In the spontaneous fermentation lower ethanol production rate was observed at the end of the fermentation process. During the sensory evaluation, fruitiness of the spontaneously fermented batch was lower, but its vegetal characteristic was pronounced. The variant with the yeast isolates from 2017 was described as smooth, and the variant with yeast isolates from 2018 was evaluated as slightly vegetal.

During alcoholic fermentation, a considerable amount of carbon dioxide (CO2) is produced, and the stream of CO2 can strip aromatic substances from the fermenting must. Aroma losses during fermentation can be significant and may lead to a reduction in wine quality. This study is focused on new fermentation gas capture technology. In the experiment, gas was captured during the fermentation of sauvignon blanc must. The concentration of individual volatile compounds in the fermentation gas was determined using gas chromatography, and the highest values were achieved by isoamyl acetate, isoamyl alcohol and ethyl decanoate. Ethyl dodecanoate achieved the lowest values of the investigated volatile substances. For sensory assessment, quantitative descriptive analysis (QDA) compared water carbonated with fermentation gas and water carbonated with commercial carbon dioxide for food purposes. Based on the results of this study, it can be concluded that the captured gas containing positive aromatic substances is suitable for the production of carbonated drinks in the food industry.

The study evaluated the effect of different fining treatments such as oenological additives and the influence of oxygen and hyperoxygenation on the phenolic and aroma composition of grape musts and wines. The oxidative method, hyperoxygenation and fining agents polyvinyl polypyrrolidone (PVPP), pea protein and chitosan were used for the removal of phenolic compounds compared to the control experiment. The content of phenolic substances was determined by high performance liquid chromatography. A total of 24 volatiles—higher alcohols, ethyl esters and acetate esters were determined using gas chromatography-mass spectrometry. A lower concentration of caftaric acid was observed in hyperoxygenated (0.21 mg·L−1), oxidated (0.37 mg·L−1), PVPP-treated (35.50 mg·L−1), pea protein-treated (42.56 mg·L−1) and chitosan-treated variants (44.40 mg·L−1), in contrast to the control must (caftaric acid 50.38 mg·L−1). In the final wine, the results were similar with a lower concentration of caftaric acid in hyperoxygenated (7.10 mg·L−1), oxidated (14.88 mg·L−1), PVPP-treated (23.49 mg·L−1), pea protein-treated (29.49 mg·L−1) and chitosan-treated variant (30.02 mg·L−1), in contrast to the control wine (caftaric acid 32.19 mg·L−1).

A wine’s aroma profile is an important part of the criteria affecting wine acceptability by consumers. Its characterisation is complex because volatile molecules usually belong to different classes such as alcohols, esters, aldehydes, acids, terpenes, phenols and lactones with a wide range of polarity, concentrations and undesirable off-aromas. This review focused on mechanisms and conditions of the formation of individual aroma compounds in wine such as esters and higher alcohols by yeast during fermentation. Additionally, aroma losses during fermentation are currently the subject of many studies because they can lead to a reduction in wine quality. Principles of aroma losses, their prevention and recovery techniques are described in this review.

This paper evaluates the effect of must hyperoxygenation on final wine. Lower concentrations of caftaric acid (0.29 mg·L−1), coutaric acid (1.37 mg·L−1) and Catechin (0.86 mg·L−1) were observed in hyperoxygenated must in contrast to control must (caftaric acid 32.78 mg·L−1, coutaric acid 5.01 mg·L−1 and Catechin 4.45 mg·L−1). In the final wine, hydroxybenzoic acids were found in higher concentrations in the control variant (gallic acid 2.58 mg·L−1, protocatechuic acid 1.02 mg·L−1, vanillic acid 2.05 mg·L−1, syringic acid 2.10 mg·L−1) than in the hyperoxygenated variant (2.01 mg·L−1, 0.86 mg·L−1, 0.98 mg·L−1 and 1.50 mg·L−1 respectively). Higher concentrations of total flavanols (2 mg·L−1 in hyperoxygenated must and 21 mg·L−1 in control must; 7.5 mg·L−1 in hyperoxygenated wine and 19.8 mg·L−1 in control wine) and polyphenols (97 mg·L−1 in hyperoxygenated must and 249 mg·L−1 in control must; 171 mg·L−1 in hyperoxygenated wine and 240 mg·L−1 in control wine) were found in both the must and the control wine. A total of 24 volatiles were determined using gas chromatography mass spectrometry. Statistical differences were achieved for isobutyl alcohol (26.33 mg·L−1 in control wine and 32.84 mg·L−1 in hyperoxygenated wine), or 1-propanol (7.28 mg·L−1 in control wine and 8.51 mg·L−1 in hyperoxygenated wine), while esters such as isoamyl acetate (1534.41 µg·L−1 in control wine and 698.67 µg·L−1 in hyperoxygenated wine), 1-hexyl acetate (136.32 µg·L−1 in control wine and 71.67 µg·L−1 in hyperoxygenated wine) and isobutyl acetate (73.88 µg·L−1 in control wine and 37.27 µg·L−1 in hyperoxygenated wine) had a statistically lower concentration.

This review is focused on the study of the effects of grape seed and skin extract (GSSE) on human health. GSSE contains high concentrations of important polyphenolic substances with high biological activity. This review is a summary of studies that investigate the effects of GSSE on diabetes mellitus, cardiovascular disease and cancer, its neuroprotective effect, and its effects on the gastrointestinal tract and other health complications related to these diseases. The results of the studies confirm that the anti-inflammatory, antiapoptotic, and pro-proliferative effects of “Vitis vinifera L.” seed extract reduce the level of oxidative stress and improve the overall lipid metabolism.

The paper deals with the study of antioxidant properties of extracts from vine seeds (Vitis vinifera L.) using spectrometric and chromatographic techniques. Ten vine varieties (Cerason, Laurot, Kofranka, Gewürztraminer, Hibernal, Blaufrankisch, Zweigeltrebe, Erilon, Palava, and Welschriesling) obtained from the years 2015, 2016, and 2017 were selected for the study. The antioxidant activity was determined spectrophotometrically using four fundamentally different methods; the content of total polyphenolic compounds was determined using the Folin–Ciocalteu method. In 2015, the content of 14 antioxidants (gallic acid, caffeic acid, coumaric acid, coutaric acid, ferulic acid, fertaric acid, trans-piceid, trans-piceatannol, rutin, quercetin-3-β-d-glucoside, quercitrin, myricetin, catechin, and epicatechin) were studied. The results of the study show the high content of antioxidant components in grape seeds and the differences in content in individual varieties and in individual years.

This study aimed to determine the concentrations of the lignans pinoresinol, secoisolariciresinol, matairesinol and isolariciresinol in white wines aged in twelve different oak barrels originating from different cooperages and regions and with different toasting levels. In a two-year experiment the influence of oak barrels and of variety on lignan content was monitored. The results of this study show that the use of oak barrels affects only syringaresinol concentrations. Wines from low-releasing barrels contained mean concentrations of 20-50 ng/ml of syringaresinol, while wines from high-releasing barrels contained mean concentrations of 140-160 ng/ml of syringaresinol. Wines from the other barrels contained mean concentrations of 70-100 ng/ml of syringaresinol. The amounts of matairesinol and pinoresinol were affected by grapevine cultivar. In Veltliner Grün, the mean matairesinol concentration was significantly higher than in all other cultivars except for Chardonnay (mean concentrations 11, 6 and 3-5 ng/ml in Veltliner Grün, Chardonnay and other cultivars respectively). The amounts of isolariciresinol and secoisolariciresinol and total amount of lignan aglycones were affected by the interaction of cultivar and year. The mean concentrations of both lignans and total aglycone were significantly higher in Chardonnay from 2017 (210, 120 and 460 ng/ml for isolariciresinol, secoisolariciresinol and total aglycones respectively) than in all the other samples (60-130, 0-50 and 180-280 ng/ml for isolariciresinol, secoisolariciresinol and total aglycones respectively).

This study focuses on the isolation of a consortium of microorganisms from spontaneously fermenting must that naturally contain lactic acid bacteria, non-saccharomyces yeasts, and saccharomyces yeasts. To collect the greatest diversity of microorganisms, the consortium was taken from the point of micro-sparkling. Based on the growth curves, isolation was performed using individual special nutrient media, and the isolates were subsequently multiplied in the nutrient medium. Individual isolates were then used for fermentation tests to monitor the percentage of fermented sugar and hydrogen sulphide production. The highest fermentation abilities were achieved in the isolates containing Saccharomyces cerevisiae and Zygosaccharomyces bailii. The smallest amount of ethanol was formed from the isolates containing Hanseniaspora uvarum, while Candida sake isolate produced the lowest amount of hydrogen sulphide and Zygosaccharomyces bailii produced the highest. The other isolates produced an average amount. Based on these results, a consortium containing the given isolates in a certain ratio was compiled.

In this study effects of commercial yeast preparations on the aromatic profile of Sauvignon Blanc varietal wine were investigated. Grape juice was divided to 7 experimental variants and fermented spontaneously and using 6 commercial strains of Saccharomyces cerevisiae. In final wine samples, essential analytical parameters and selected aromatic compounds were analysed. The highest content of esters was found out in samples fermented by spontaneous micro‑flora; in this case, concentrations of ethyl hexanoate, ethyl octanoate and ethyl decanoate were 682 µg/L, 735 µg/L and 162 µg/L, respectively. The highest content of acetates was recorded in samples fermented by yeast Vulcaferm Sauvignon; concentrations of isoamyl acetate, 2‑phenylethyl acetate and isobutyl acetate were 7.8 mg/L, 244 µg/L and 137 µg/L, respectively. Yeast strain suitable for cold fermentation (Oenoferm Fredo) produced high amounts of ethyl esters and acetates. As far as the sensory evaluation was concerned, the best rating got the sample fermented by these yeasts; it showed a high degree of smell and flavour cleanness as well as a very good overall harmony.