Wine Components Research Articles

High-performance bioelectronic tongue for the simultaneous analysis of phenols, sugars and organic acids in wines.

Electronic tongues have been widely used to analyze wines. However, due to the complexity of the matrix, the problem is not completely solved and further improvements are required. A high-performance potentiometric bio-electronic tongue (bio-ET) specifically devoted to the assessment of wine components is presented. The novelty of this system is due to two innovative approaches. First, the improved performance is obtained through the use of potentiometric biosensors based on carboxylated PVC membranes where enzymes specific to compounds of interest (glucose oxidase, tyrosinase, laccase and lyase) are linked covalently. Secondly, the performance is further enhanced by introducing in the PVC membrane electron mediators (AuNPs or CuPc) that facilitate the electron transfer process. Individual sensors exposed to target analytes (glucose, catechol, cysteine or tartaric acid) show a linear behavior with limits of detection in the range of 10-4 M for all the compounds analyzed, with excellent reproducibility (CV lower than 3%). Sensors combined to form a bio-ET, show excellent capabilities. Principal Component Analysis (PCA), can discriminate monovarietal white wines (PC1 77%; PC2 15%) and red wines (PC1 63%; PC2 30%). Using Partial Least Squares (PLS) the bio-ET can provide information about chemical parameters including Glucose, Total Polyphenols, Total Anthocyanins, Free SO2 , Total SO2 , Total acidity and pH with square correlation coefficients (R2 ) between 0.91 and 0.98 in calibration and between 0.89 and 0.98 in validation. This advanced instrument is able to assess the levels of seven parameters in a single measurement providing an advantageous method to the wine industry. This article is protected by copyright. All rights reserved.

Quantification of thaumatin-like proteins in white wine using MALDI-TOF mass spectrometry

The main soluble proteins in bottled wine are pathogenesis-related proteins. Their concentration is influenced by the harvesting technique used, the time of the juice exposition to grape skins and possible microbial infection of grapes. The most typical are namely chitinases and thaumatin-like proteins (TLPs), which accumulate in grapes on ripening. They show a low molecular weight of 20–35 kDa and are resistant to proteolysis as well as the acidic pH of wine. Chitinases are considered the primary cause of heat-induced haze formation because of their irreversible denaturation and aggregation. This process can additionally be affected by the non-protein wine components. We focused on the development of a fast quantification method for wine TLPs using matrix-assisted laser desorption/ionization mass spectrometry. White wine samples were analyzed directly, after dialysis or they were subjected to protein concentrating procedures before the measurements. MS-based quantification was achieved by comparing the peak areas of an internal standard (cytochrome c, thaumatin or myoglobin) and TLPs in the acquired mass spectra. The content of TLPs in commercial wines was determined at milligrams per liter. Chitinases could not be quantified in this way because of a low concentration in the analyzed bentonite-fined wines resulting in missing spectral signals. Anyway, this procedure becomes an alternative to common quantification methods based on liquid chromatography.

Insights into microbial communities and metabolic profiles in the traditional production of the two representative Hongqu rice wines fermented with Gutian Qu and Wuyi Qu based on single-molecule real-time sequencing

Hongqu rice wine, a famous traditional fermented alcoholic beverage, is brewed with traditional Hongqu (mainly including Gutian Qu and Wuyi Qu). This study aimed to compare the microbial communities and metabolic profiles in the traditional brewing of Hongqu rice wines fermented with Gutian Qu and Wuyi Qu. Compared with Hongqu rice wine fermented with Wuyi Qu (WY), Hongqu rice wine fermented with Gutian Qu (GT) exhibited higher levels of biogenic amines. The composition of volatile flavor components of Hongqu rice wine brewed by different fermentation starters (Gutian Qu and Wuyi Qu) was obviously different. Among them, ethyl acetate, isobutanol, 3-methylbutan-1-ol, ethyl decanoate, ethyl palmitate, ethyl oleate, nonanoic acid, 4-ethylguaiacol, 5-pentyldihydro-2(3H)-furanone, ethyl acetate, n-decanoic acid etc. were identified as the characteristic aroma-active compounds between GT and WY. Microbiome analysis based on high-throughput sequencing of full-length 16S rDNA/ITS-5.8S rDNA amplicons revealed that Lactococcus, Leuconostoc, Pseudomonas, Serratia, Enterobacter, Weissella, Saccharomyces, Monascus and Candida were the predominant microbial genera during the traditional production of GT, while Lactococcus, Lactobacillus, Leuconostoc, Enterobacter, Kozakia, Weissella, Klebsiella, Cronobacter, Saccharomyces, Millerozyma, Monascus, Talaromyces and Meyerozyma were the predominant microbial genera in the traditional fermentation of WY. Correlation analysis revealed that Lactobacillus showed significant positive correlations with most of the characteristic volatile flavor components and biogenic amines. Furthermore, bioinformatical analysis based on PICRUSt revealed that microbial enzymes related to biogenic amines synthesis were more abundant in GT than those in WY, and the enzymes responsible for the degradation of biogenic amines were less abundant in GT than those in WY. Collectively, this study provides important scientific data for enhancing the flavor quality of Hongqu rice wine, and lays a solid foundation for the healthy and sustainable development of Hongqu rice wine industry.

Comprehensive Evaluation of Ten Actinidia arguta Wines Based on Color, Organic Acids, Volatile Compounds, and Quantitative Descriptive Analysis.

Actinidia arguta wine is a low-alcoholic beverage brewed from A. arguta with a unique flavor and sweet taste. In this study, the basic physicochemical indicators, color, organic acid, and volatile aroma components of wines made from the A. arguta varieties 'Kuilv', 'Fenglv', 'Jialv', 'Wanlv', 'Xinlv', 'Pinglv', 'Lvbao', 'Cuiyu', 'Tianxinbao', and 'Longcheng No.2' were determined, and a sensory evaluation was performed. The findings show that 'Tianxinbao' produced the driest extract (49.59 g/L), 'Kuilv' produced the most Vitamin C (913.46 mg/L) and total phenols (816.10 mg/L), 'Jialv' produced the most total flavonoids (477.12 mg/L), and 'Cuiyu' produced the most tannins (4.63 g/L). We analyzed the color of the A. arguta wines based on CIEL*a*b* parameters and found that the 'Kuilv' and 'Longcheng No.2' wines had the largest L* value (31.65), the 'Pinglv' wines had the greatest a* value (2.88), and the 'Kuilv' wines had the largest b* value (5.08) and C*ab value (5.66) of the ten samples. A total of eight organic acids were tested in ten samples via high-performance liquid chromatography (HPLC), and we found that there were marked differences in the organic acid contents in different samples (p < 0.05). The main organic acids were citric acid, quinic acid, and malic acid. The aroma description of a wine is one of the keys to its quality. A total of 51 volatile compounds were identified and characterized in ten samples with headspace gas chromatography-ion mobility spectrometry, including 24 esters, 12 alcohols, 9 aldehydes, 3 aldehydes, 2 terpenes, and 1 acid, with the highest total volatile compound content in 'Fenglv'. There were no significant differences in the types of volatile compounds, but there were significant differences in the contents (p < 0.05). An orthogonal partial least squares discriminant analysis (OPLS-DA) based on the odor activity value (OAV) showed that ethyl butanoate, ethyl pentanoate, ethyl crotonate, ethyl isobutyrate, butyl butanoate, 2-methylbutanal, ethyl isovalerate, and ethyl hexanoate were the main odorant markers responsible for flavor differences between all the A. arguta wines. Sensory evaluation is the most subjective and effective way for consumers to judge A. arguta wine quality. A quantitative descriptive analysis (QDA) of the aroma profiles of ten grapes revealed that the 'fruity' and 'floral' descriptors are the main and most essential parts of the overall flavor of A. arguta wines. 'Tianxinbao' had the highest total aroma score. The flavor and quality of A. arguta wines greatly depend on the type and quality of the A. arguta raw material. Therefore, high-quality raw materials can improve the quality of A. arguta wines. The results of the study provide a theoretical basis for improving the quality of A. arguta wines and demonstrate the application prospects of HS-GC-IMS in detecting A. arguta wine flavors.

Evaluation of the Quality of Selected White and Red Wines Produced from Moravia Region of Czech Republic Using Physicochemical Analysis, FTIR Infrared Spectroscopy and Chemometric Techniques.

The FTIR-ATR method coupled with the multivariate analysis of specific spectral areas of samples was developed to characterize two white grape varieties (Sauvignon Blanc and Hibernal) and two blue grape varieties (André and Cabernet Moravia) of wine planted and harvested in the Moravia region, Czech Republic. Principal component analysis and hierarchical cluster analysis were performed using fingerprint regions of FTIR spectra for all wines. The results obtained by principal component analysis in combination with linear discriminant analysis (PCA-LDA) scores yielded clear separation between the four classes of samples and showed very good discrimination between the wine samples, with a 91.7% overall classification rate for the samples. The conducted FTIR spectroscopy studies coupled with chemometrics allowed for the swift analysis of multiple wine components with minimal sample preparation. These methods can be used in research to improve specific properties of these wines, which will undoubtedly enhance the quality of the final wine samples obtained.

Convolution Neural Network-Assisted Smart Fluorescent-Tongue Based on Lanthanide Ion-Induced Forming MOF/HOF Composite for Differentiation of Flavor Compounds and Wine Identification.

Wine flavor is a vital quality characteristic in wine, influenced by those flavor components with low sensory thresholds. It is crucial to recognize and classify the wine components related to their flavor contribution. The integration of fluorescent sensors and artificial intelligence shows huge potential in flavor recognition by emulation of the gustatory perception system. Meanwhile, achieving information identification of wine based on multiple information barcodes has hopeful applications in anticounterfeiting. In this study, we present a simple method in which organic linkers are weaved into a hydrogen-bonded organic framework (HOF) for the available transformation of a metal-bonded organic framework (MOF) induced by lanthanide ions (Ln3+). The fluorescent Ln-MOF/HOF composite exhibits high sensitivity, rapid response, and good recyclability for detecting seven flavor compounds in wine, including tannic acid, ionone, vanillin, anethole, anisaldehyde, hydroxybenzaldehyde, and 4-hydroxy-2-methylacetophenone. Depending on its satisfactory detectability, a novel strategy is provided in which a fluorescent sensor is able to function as a smart fluorescent-tongue (F-tongue) by the aid of convolutional neural network to differentiate these seven flavor compounds. In addition, the Ln-MOF/HOF composite has been used to prepare multiple information barcodes for wine information identification on the basis of dynamic fluorescence response toward tannic acid. The mimetic gustatory perception system developed in this study may offer a promising strategy for flavor recognition in food and further food anticounterfeiting.

Role of p-Coumaric Acid and Micronutrients in Sulfur Dioxide Tolerance in Brettanomyces bruxellensis

Role of p-Coumaric Acid and Micronutrients in Sulfur Dioxide Tolerance in Brettanomyces bruxellensis

Paper chromatography approach for the assessment of interaction between red wine and whole saliva

In-mouth interaction of red wine compounds with salivary proteins is a primary event allegedly responsible for eliciting the mouth-feel sensation of astringency. Those interactions have been currently associated with precipitation of salivary protein/polyphenol complexes. However, such single physicochemical evidence for interaction does not account for the complexity of astringency. This study aimed to develop a paper chromatography method to assess interactions between red wine and the salivary protein fraction using stepwise series of red wine/saliva binary mixtures from 100% wine to 100% saliva (“Alpha and Omega series”). Aliquots of each one of the mixtures were spotted on a cellulose membrane to scrutinize independently the distribution areas of wine components (naturally pink-colored) and salivary protein (stained blue in Coomassie Brilliant R-250). This double target detection revealed interactions between saliva and red wine components along most of the quantitative Alpha and Omega series, a point of equivalence corresponding to maximum interactivity for both complex reactants and a non-diffusible sub-fraction of saliva displaying the highest interactivity. The results indicate a novel way to assess quantitatively physicochemical interactions between red wines and human saliva but also provide new lights to approach the identification of molecular salivary structures involved in triggering astringency.

Adsorption Capabilities of Fungoid Chitosan Toward Organic Acids in Model Solutions and White Wine

In oenology, fungoid chitosan (CH) can be used as an adjuvant for microbial control, haziness prevention, metal chelation, and ochratoxin removal. In acidic media (such as wine), CH can ionise and interact with charged compounds, giving rise to a series of adsorption and/or removal phenomena, some of which potentially impairing the overall quality of wines. In this context, it is worth noting that the interaction between CH and acidic components of wines has been poorly studied so far, and detailed information on this subject is still lacking. To study those interactions, different doses of chitosan (0.5; 1.0; 2.0 g/L) were dispersed in hydro-alcoholic solution (HS), synthetic wine solution (SW), and white wine (W). Results demonstrated that the remotion of tartaric acid and the change of pH were strongly affected by the matrix and dosage. In W and SW, chitosan was found to adsorb tartaric acid up to about 200 mg/g and 350 mg/g CH, respectively. Accordingly, pH values increased; however, the magnitude depended on the matrix as a consequence of different buffer capacities. Interestingly, even in the absence of tartaric acid (e.g. in HS samples) CH addition caused a pH increase (up to 1.2 units for 2 g/L CH addition) which demonstrated that pH variations may not only depend on the amount of organic acids adsorbed. The chitosan dispersed in W showed the highest average diameter D [3,2] (127.96 μm) compared to the ones dispersed in SW (120.81 μm) and in HS (116.26 μm), probably due to the presence of organic acids on the polymer surface. The minor removal of tartaric acid in W compared to SW could probably depend on the competitive adsorption onto chitosan of other families of compounds present in wine such as polyphenols. The data suggested that chitosan addition could affect the pH and organic acid concentration of all matrices, depending on the doses and composition of the solutions.

Metagenomic analysis of the relationship between the microorganisms and the volatiles' development in the wines during spontaneous fermentation from the eastern foothills of the Ningxia Helan mountains in China.

The natural fermentation of multispecies microbial communities is responsible for unique flavors of winery regions of the eastern foothills of the Ningxia Helan Mountains in China. However, the participation of different microorganisms in the metabolic network for the development of important flavor substances is not clearly defined. Microbial population and diversity on different fermentation phases of Ningxia wine were analyzed by metagenomic sequencing approach. Gas chromatography-mass spectrometry and ion chromatography were used to identify flavor components, and 13 esters, 13 alcohols, nine aldehydes and seven ketones were detected in volatile substances with odor activity values > 1, and eight organic acids were detected as important flavor components in young wine. Thus, 52 238 predicted protein-coding genes from 24 genera were identified in the Kyoto Encyclopedia of Genes and Genomes level 2 pathways of global and overview maps, and the genes were primarily involved in amino acid metabolism and carbohydrate metabolism. Major microbial genera (Saccharomyces, Tatumella, Hanseniaspora, Lactobacillus, and Lachancea) were closely related to self-characteristic compound metabolism and further contributed to wine flavor. This study clarifies the different metabolic roles of microorganisms in flavor formation during Ningxia wine spontaneous fermentation. Saccharomyces, dominant fungi involved in glycolysis and pyruvate metabolism, produces not only ethanol but also two important precursors, pyruvate and acetyl-CoA, which are necessary for the tricarboxylic acid cycle, fatty acid metabolism, amino acid metabolism, and flavor formation. Lactobacillus and Lachancea, dominant bacteria involved in lactic acid metabolism. Tatumella, dominant bacteria involved in amino acid metabolism, fatty acid metabolism, and acetic acid metabolism to produce esters in the Shizuishan City region samples. These findings provide insights into the use of local functional strains to generate unique flavor formation, as well as improved stability and quality, in wine production. © 2023 Society of Chemical Industry.

Volatile components of Pelaverga red wines from Piedmont (Italy)

AbstractBackgroundThe characterization of a typical red wine from Piedmont (north‐west Italy), Pelaverga, was performed by means of headspace solid phase microextraction coupled to gas chromatography–mass spectrometry. Two different kinds of Pelaverga are known, hystorical and Verduno, which differ with the area of production. The main volatile compounds of the wine were identified and semi‐quantified. Principal components analysis (PCA) was performed to identify possible clusters among the different samples analyzed.ResultsForty‐eight volatile compounds were unambiguously identified in the wines sampled. The two types of Pelaverga analyzed displayed a very similar volatile profile. The most abundant volatile compounds were two esters, ethyl octanoate and diethyl succinate, and two alcohols, isoamyl alcohol and ethyl phenyl alcohol. Few varietal compounds were detected, probably due to their low concentration; among these, we were not able to detect rotundone, which is reported to impart characteristic spicy notes to this kind of wine. Application of PCA did not allow to differentiate between the two types of Pelaverga on the basis of their volatile profile.ConclusionThe present work is, to the best of our knowledge, the first complete report about the volatile profile of Pelaverga wines and represents the first step of a research project aiming at characterizing food products from Piedmont on the basis of chemical parameters. Differentiation between the two types of Pelaverga will likely require the determination of different chemical parameters in conjunction with volatile compounds.

Wine component tracing method based on near infrared spectrum fusion machine learning

An intelligent wine detection and traceability method based on infrared spec-troscopy and machine learning is proposed, in order to meet the needs of online rapid nondestructive testing of wine. On the basis of extracting infrared spectrum of wine, the principal component analysis (PCA) – support vector machine (SVM) model was modified by chemometrics. A total of 300 grape wine samples were collected from six production areas. The composition of the samples was analyzed by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). According to the experimental results, indole, sulfacetamide and caffeine were selected as characteristics of different origins. Near infrared spectral wavelengths of wine samples were compressed between 900 and 2,500 nm. The ranges of 1,000 nm ~ 1,400 nm and 1,500 nm ~ 1800 nm were selected for PCA principal component analysis and key spectral wavelengths were extracted. The unsupervised learning model of SVM is used to classify and identify key spectral wavelengths. The experimental results show that the algorithm has higher classification accuracy than traditional PCA-LDA, PCA and other algorithms. The classification accuracy of the algorithm is improved from 98.3 to 99.75%. The improved PCA-SVM algorithm can achieve fast and loss-less source tracing of wine.

Chemical Profiling of Wines Produced in Bulgaria and Distinction from International Grape Varieties.

Distinguishing the botanical and geographical origin of wine is important to prevent wine adulteration and to determine its quality. The combined use of 1H NMR profiling and chemometrics allows the quantification of 31 common organic components in the NMR spectra of 70 wines from different sources. Using the NMR metabolomics approach, a successful differentiation of wines produced from Bulgarian and international grape varieties is achieved using linear discriminant analysis. Wines produced from typical local grape varieties contain higher average amounts of galacturonic, malic, tartaric, and succinic acid, alanine, choline, several alcohols, and saccharides arabinose, galactose, and sucrose than imported wine assortments. A practical decision tree is proposed for distinguishing 15 different grape varieties based on the amounts of the common wine components. An example of distinction of real from diluted wine via creation of a PLS-DA model is presented. Wines from the two subregions officially recognized by the EU at the Protected Geographical Indication (PGI) level are unequivocally recognized.

Application of salicylic acid to cv. Muscat Hamburg grapes for quality improvement: Effects on typical volatile aroma compounds and anthocyanin composition of grapes and wines

Aromas and anthocyanins are important factors affecting grapes and wines quality. Monoterpenes are regarded as typical volatile aroma compounds in Muscat Hamburg grapes. In this study, we determined the effects of exogenous salicylic acid (SA) on anthocyanins and monoterpene components of Muscat Hamburg (Vitis vinifera) berries and wines. Berries were treated with aqueous solutions of SA (0.0, 50, 100 and 200 mg/L) at E-L 34 (berry color change stage) during 2018 and 2019 seasons. 50 mg/L salicylic acid (SA50) significantly increased the sum of anthocyanins contents in ripe berries, while 100 mg/L and 200 mg/L salicylic acid had the opposite effect. Additionally, SA50 significantly promoted the free or bound monoterpenes accumulation in mature grapes. The concentrations of geraniol, neral, geranic acid, nerol, nerol oxide, and phellandrene were higher in the wine produced from SA50 treatment grapes than in the wine produced from control groups. The SA50 treatments increased the transcription of some key genes related to monoterpene biosynthesis, namely, VviPNLinNer1, VviPNLinNer2, VviPNLNGl2, VviPNLNGl4, VviTer, and VviGT14, which accelerated the synthesis and accumulation of monoterpene components in grapes. Overall, these study findings can provide fundamental knowledge for future improvements to grape aromas and anthocyanins.

لێكچواندنی شه‌راب و پێكهاته‌كانی له‌ ده‌قه ‌شیعرییه‌كانی حافز و مەلای جزیریدا

Comparison is one of the psychological subjects that most of the classical poets, to decorate the poetic taste and give poetry, decorated their poetic texts with this art, this art belongs to the science of explanation Kurdish Kurdish, as one of the most prominent pillars of classical Kurdish literature is considered the old stage, the use of such arts not only ignored, but very carefully and more intensively and artistically with a background of rhetoric has strengthened and more effective. They have divided poetry into imaginary structures, using them as satisfied in examples, have been able to present poetry in his poems, by taking the idea of this kind of art in some of their predecessors to promote their poetry and make fewer inventions in this field. First of all, what is questionable in this study is how they used the analogies and compositions of wine. The most important historical relationship reflected in the poet's poems. In the first part, we have focused on the art of comparison from the perspective of text poetry. Keywords: Mullah Jaziri and Hafiz Shirazi, explanation, analogy, wine, wine components.

HPLC Analysis of Polyphenols Derived from Hungarian Aszú from Tokaj Wine Region and Its Effect on Inflammation in an In Vitro Model System of Endothelial Cells.

Many studies have been published in recent years regarding the fact that moderate wine consumption, as a part of a balanced diet can have a beneficial effect on human health. The biologically active components of wine continue to be the subject of intense research today. In this study, the bioactive molecules of Hungarian aszú from the Tokaj wine region were analyzed using high-performance liquid chromatography (HPLC) and investigated in an in vitro model system of endothelial cells induced by bacterial-derived lipopolysaccharide. The HPLC measurements were performed on a reversed phased column with gradient elution. The non-cytotoxic concentration of the active substance was determined based on 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT)-, apoptosis, and necrosis assays. The antioxidant effect of the extract was determined by evaluating its ability to eliminate ROS. The expressions of the interleukin-(IL)1α, IL1-β, IL-6, and IL-8 pro-inflammatory cytokines and nitric oxide synthase (eNOS) at the mRNA level were evaluated using a quantitative polymerase chain reaction (qPCR). We found that the lipopolysaccharides (LPS)-induced increases in the expressions of the investigated cytokines were significantly suppressed by Hungarian aszú extract, excluding IL-6. In our experimental setup, our treatment had a positive effect on the eNOS expression, which was impaired as a result of the inflammatory manipulation. In our experimental model, the Hungarian aszú extract decreased the LPS-induced increases in the expression of the investigated cytokines and eNOS at the mRNA level, which presumably had a positive effect on the endothelial dysfunction caused by inflammation due to its strong antioxidant and anti-inflammatory effects. Collectively, this research contributes to a more thorough understanding of the bioactive molecules of aszú from the Tokaj wine region.

Pilot Scale Evaluation of Wild Saccharomyces cerevisiae Strains in Aglianico

In winemaking, the influence of Saccharomyces cerevisiae strains on the aromatic components of wine is well recognized on a laboratory scale, but few studies deal with the comparison of numerous strains on a pilot scale fermentation. In this scenario, the present work aimed to validate the fermentative behavior of seven wild S. cerevisiae strains on pilot-scale fermentations to evaluate their impact on the aromatic profiles of the resulting wines. The strains, isolated from grapes of different Italian regional varieties, were tested in pilot-scale fermentation trials performed in the cellar in 1 hL of Aglianico grape must. Then, wines were analyzed for their microbiological cell loads, main chemical parameters of enological interest (ethanol, total sugars, fructose, glucose, total and volatile acidity, malic and lactic acids) and volatile aroma profiles by GC/MS/SPME. Seventy-six volatile compounds belonging to six different classes (esters, alcohols, terpenes, aldehydes, acids, and ketones) were identified. The seven strains showed different trends and significant differences, and for each class of compounds, high-producing and low-producing strains were found. Since the present work was performed at a pilot-scale level, mimicking as much as possible real working conditions, the results obtained can be considered as a validation of the screened S. cerevisiae strains and a strategy to discriminate in real closed conditions strains able to impart desired wine sensory features.

Study of the influence of fermentation conditions on the content of aroma-forming substances in young red wines

One of the main requirements for young wines is preservation the qualities of the grapes, including the bright varietal aroma characteristic of essential oils concentrated in the grape skins. At the same time, in the formation of the aroma of wine, substances synthesized by the enzyme systems of yeast cells are involved in the process of alcoholic fermentation. The main factors influencing the formation and ratio of aroma-forming substances in wine are the composition of the substrate, the race of yeast and the conditions for the fermentation process. Therefore, studies of the influence of the conditions of the fermentation process in the production of young red wine materials on the chemical composition of the aroma-forming components of wine are relevant. The analysis of the data obtained indicates the influence of the methods of carrying out the alcohol process on the content of aroma-forming compounds: aldehydes, ketones, higher and polyhydric alcohols, esters and fatty acids. It has been shown that the fermentation of the pulp wort, unlike carbon dioxide maceration, leads to a greater accumulation of oxidation products: acetaldehyde, acetoin and diacetyl, and also contributes to a higher content of higher alcohols. Under conditions of carbon dioxide maceration, a significant accumulation of aromatic alcohol – phenylethanol occurs. The conducted studies have shown that the use of carbon dioxide maceration using the Moldova grape variety generally has led to a significantly lower formation of oxidation products of both wort components and fermentation products. The additional introduction of carbon dioxide contributed to a decrease in the RH potential of the fermenting wort, which stimulated the accumulation of substances in a reduced form. At the same time, the content of esters in the case of artificial maceration is higher than under normal conditions, which indicates more intense enzymatic esterification reactions.It has been established that carbon dioxide maceration, in comparison with the classical processing of grapes, contributes to a greater formation and extraction of favorable aromatic components, and the additional introduction of carbon dioxide enhances this process.

Effects of Different Brewing Technologies on Polyphenols and Aroma Components of Black Chokeberry Wine

The black chokeberry is a shrub of the Rosaceae family, which is characterized by strong acidity and astringency and is widely processed into wine and alcoholic beverages. However, due to the characteristics of black chokeberries, the wine brewed by traditional methods often has a strong sour taste, weak aroma, and poor sensory quality. In order to improve the sensory quality and explore the effects of different brewing technologies on polyphenols of black chokeberry wine, five brewing technologies (traditional fermentation, frozen fruit fermentation, co-fermentation, carbonic maceration, and co-carbonic maceration) were used in this study. The results showed that compared with the traditional method, the four alternative brewing technologies could reduce acidity, increase the contents of several major polyphenols, and enrich floral scents and fruity aroma, thus significantly improving the sensory qualities of black chokeberry wine. The proposed brewing technologies would be applied to the production of quality black chokeberry or other fruit wines.

Comparison and Intercorrelation of Various Bentonite Products for Oenological Properties, Elemental Compositions, Volatile Compounds and Organoleptic Attributes of White Wine.

Bentonite fining is one of the generally applied wine-making technological elements that may seriously affect wine components. The aim of this study was (i) to investigate the effect of 21 bentonite products on eight oenological parameters, 19 elements, 21 volatile organic compounds (VOCs) and 10 organoleptic properties of white wine; and (ii) to quantify intercorrelations among the parameters separately for each of the four quality attributes. Among oenological parameters, sugar, acidity, malic-, lactic-, citric acid and total phenol contents were significant among several bentonite products. The amounts of elements were the lowest in the control wine treatments (with exceptions of, e.g., Ni and Cu); and these values were significantly different from several bentonite products. The relative presence of the VOCs was above 100% for most VOCs, but it was below 100% for 1-propanol, 4-amino-1,5-pentandioic acid and butane-dioic acid, and diethyl ester in all treatments. For organoleptic parameters, the values of clearness, colour, flavour intensity and taste persistency was the lowest in the control wine treatment, while the values of flavour character, flavour quality, taste intensity, taste character, and overall harmony were the highest for the bentonite products of AP, EBE, M-SA, EBE, EBE, respectively. Results of correlation and factor analyses showed strong intercorrelative effects of bentonite fining on the four quality attributes. In conclusion, this study can help in the proper choice of a specific bentonite product in relation to complexity effects of bentonite fining.