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This study aimed to evaluate bioactive properties of Teran red wine by-products (grape skins, seeds, and wine lees) from six vinification treatments, including a control (7-day standard maceration). Pre-fermentative cryomaceration (8 °C; 48 h) and hot maceration (50 °C; 48 h), followed by the 13-day (CS15; C15; H15) and 28-day (C30; H30) period, considering fermentation/maceration and extended post-fermentative maceration, were conducted. In CS15, the saignée procedure was applied before fermentation/maceration. After maceration, the separation of by-products was performed, followed by lyophilization and solid–liquid extraction. Then, individual phenols were analyzed using high-performance liquid chromatography (HPLC), and total phenolic content (TPC) and antioxidant activity (FRAP) were analyzed using UV/Vis spectrophotometry. The results showed grape skins and wine lees in all treatments had significantly increased TPC and FRAP values compared to the control. The highest concentration of total phenols (HPLC) in grape skins was found in CS15, at 978.54 mg/100 g DW. In wine lees, the highest concentration of total phenols was detected in the 30-day maceration treatments, at 582.04 mg/100 g DW in C30, and 595.83 mg/100 g DW in H30, despite the pre-fermentative procedure. In grape seeds, the highest concentration of total phenols was found in the control (K7), at 432.42 mg/100 g DW. Pre-fermentative heating together with extended 30-day maceration (H30) strongly reduced the total levels of phenols (HPLC and TPC) in grape seed samples. The findings implied an evident impact of pre- and post-fermentative technologies on phenols and antioxidant activity in wine by-products of cv. Teran (Vitis vinifera L.). [ABSTRACT FROM AUTHOR]

The yeast Lachancea thermotolerans has the ability to produce notable amounts of lactic acid and reduce alcoholic strength in fermentation, so it has a considerable potential for mitigating negative impacts of climate changes in winemaking. In this study, a treatment with L. thermotolerans and Saccharomyces cerevisiae in sequential inoculation was compared to a control S. cerevisiae monoculture fermentation of Malvazija istarska (aka Malvasia Istriana) white grape must. Standard physico-chemical parameters of the obtained wines were determined by the OIV methods. Targeted (GC/FID and GC/MS) and untargeted (GC×GC/TOF-MS) gas chromatographic techniques were combined for the analysis of volatile compounds. Phenolic compounds were analyzed by UPLC/QqQ-MS/MS, and proteins by RP-HPLC-DAD, while a sensory analysis of wines was performed by a panel of trained and certified tasters. L. thermotolerans co-fermentation treatment increased the concentration of lactic acid and decreased alcoholic strength. L. thermotolerans increased the concentrations of geraniol, β-ionone, isobutanol, isobutyric acid, ethyl isobutyrate, several major acetates, ethyl lactate, and diethyl succinate, followed by many minor compounds. This wine also contained more hydroxycinnamoyl tartrates, while control S. cerevisiae wine had higher levels of free hydroxycinnamates. The effects on PR proteins were minor. L. thermotolerans co-fermentation slightly enhanced the sensory perception of tropical fruit, herbaceous, tobacco, and buttery odor notes, as well as fullness of body. With the largest number of identified volatile compounds up to date and other results obtained, this study contributes to the better understanding of oenological and especially aromatic potential of L. thermotolerans in white wine production. [ABSTRACT FROM AUTHOR]

Featured Application: Featured Application: This study provides a comprehensive analysis of the impact of various vinification techniques, including prolonged maceration, pre-fermentation heating, and barrel aging, on the volatile aroma profile and sensory characteristics of Teran red wine. Teran (Vitis vinifera L.) is the most widespread red autochthonous variety in Istria, traditionally grown in the north Adriatic area, including the Croatian Istria viticultural subregion. As a key grapevine variety in viticulture across these regions, understanding the impact of the investigated techniques is crucial for enhancing its unique characteristics and market value. These insights can be directly applied by winemakers to optimize and tailor wine production processes, enhancing desirable aroma attributes and sensory qualities to meet specific market demands. The findings offer practical guidelines for producing wines with distinct and appealing aromatic profiles, aiding in product differentiation and improving overall wine quality. This study investigates the effect of prolonged maceration, pre-fermentation heating, and barrel aging on the volatile aroma profile and sensory characteristics of Teran wine. The vinification processes included a control treatment (7-day maceration, TM7-Y; Y—young wine), 10-day maceration (TM10-Y), 21-day post-fermentation maceration (TM21-Y), and 48-h pre-fermentation heating at 45 °C followed by 8-day maceration (TPHT-Y). All wines were then aged in oak barrels for six months, resulting in TM7-A, TM10-A, TM21-A, and TPHT-A wines (A—aged wine). Volatile compounds were extracted using headspace solid-phase microextraction (HS-SPME) and analyzed by gas chromatography/mass spectrometry (GC/MS), while sensory profiles were evaluated using quantitative descriptive analysis (QDA). TPHT-Y and TM21-Y treatments reduced several groups of free volatile compounds while enhancing sensory properties, with TM21-Y wines notably exhibiting pronounced dried fruit notes, likely due to high β-damascenone concentrations. Conversely, TM10-Y and TM7-Y treatments resulted in significantly higher concentrations of the most volatile aroma compounds. Aging in oak barrels significantly increased the levels of particular free volatile compounds like C13-norisoprenoids, volatile phenols, furans, and lactones. It also enhanced sensory quality, with fruity aromas prominent across all treatments, and TM21-A and TPHT-A wines showing strong dried fruit, jam, and liqueur notes. This study offers valuable insights into tailoring wine aromas and sensory attributes through specific vinification techniques, contributing to a more refined approach to optimizing wine production. In conclusion, the findings highlight the importance of maceration and aging techniques in developing complex and desirable wine profiles, offering practical guidance for improving Teran wine quality. [ABSTRACT FROM AUTHOR]

Biska, a traditional Istrian herbal spirit, is produced by macerating mistletoe leaves and twigs in a water–ethanol base, usually grape marc spirit. The aim of this study was to determine the optimal mistletoe maceration parameters (ethanol content, concentration of plant material, and duration) for the production of biska, which have not yet been the subject of scientific research. The prepared mistletoe macerates and the collected biska samples were subjected to phenolic compound characterization, including total phenolic content (TPC), total flavonoid content (TFC), and polyphenolic profile, by ultra-high-performance liquid chromatography coupled with mass spectrometry (UPLC-ESI-MS2). In addition, the macerates and the biska samples were analyzed for their biological properties: antioxidant and antiproliferative activity. The results showed that both the macerates and the biska samples contain phenolic compounds of mistletoe such as phenolic acids, flavonoids, and coumarins, which contribute to the observed biological activities—significant antioxidant activity and antiproliferative effect. By applying the maceration parameters, which yielded the highest content of phenolic compounds as well as volatile aromatic compounds (40–80 g/L of mistletoe, 40–55% v/v ethanol, and 21 days' maceration time), the production process can be improved to produce biska with better aromatic and biological properties. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the impact of early leaf removal (ELR) and cluster thinning (CT) on the phenolic composition of cv. Teran berries and wines, and the sensory profile of wines at 6 and 24 months after fermentation. Although only ELR increased the concentration of total anthocyanins in the berries as compared to the untreated control (UC), both ELR and CT had higher concentration of total anthocyanins and greater colour intensity in the resultant wines than the UC. Similar effects were obtained with total phenolics in the berries and the wines; while CT obtained higher concentration of total phenolics in the berries than UC only in one season, same treatment obtained higher concentration of total phenolics in the wine in both seasons as compared to UC. Only minor sensory differences in wines were obtained at the age of 6 months, while treatments were highly discriminated 24 months after fermentation, when both ELR and CT wines had more enhanced fruitiness, aromatic intensity, complexity, body, balance and wine overall quality than UC. The obtained results indicate that adequate wine aging period is needed for a relevant assessment of the impact of vineyard management practices on wine sensory characteristics.

Six different vinification treatments, including a control treatment (7-day standard maceration) (K7), were performed to study the effects of non-standard techniques on bioactive compounds and sensory attributes of Teran red wine. Pre-fermentative mash cooling (8 °C; 48 h) and heating (50 °C; 48 h) followed by prolonged post-fermentative maceration of 13 days (C15;H15) or 28 days (C30;H30) were applied. In another treatment, after cooling, saignée was performed followed by 13-day prolonged maceration (CS15). Wine phenols and vitamins were analyzed by HPLC-DAD-FLD, minerals by ICP-OES, and sensory analysis was performed using the QDA and 100-point O.I.V./U.I.O.E. methods. Obtained results showed total phenolic concentration was the highest in the H30 treatment. The concentration of anthocyanins, flavan-3-ols and phenolic acids was significantly higher in wines of all vinification techniques compared to the control. Stilbene content was highly affected by pre-fermentative heating. Treatments CS15, H15, C30 and H30 resulted in the highest scores by both the QDA and 100-point sensory methods. The obtained results suggest that advanced non-standard vinification techniques have a significant impact on Teran wine by enhancing its composition of bioactive compounds and improving its sensory profile, which gives it an additional market value. Furthermore, a comprehensive comparison of such techniques applied simultaneously in one study is of substantial importance for additional research in wine production. [ABSTRACT FROM AUTHOR]

To investigate the effects of the application of bentonite, tannins, and their combination in alcoholic fermentation, Malvazija istarska (Vitis vinifera L.) white grape must was treated with 95 g/L of bentonite, 25 g/L of a hydrolysable tannin preparation, while the third treatment received the aforementioned doses of both agents. Control grape must was fermented without bentonite and exogenous tannins. All of the produced wines were additionally fined after fermentation with doses of bentonite needed to achieve complete protein stability. Wines were analyzed both after fermentation and after additional bentonite fining. Standard physicochemical parameters were determined by the OIV methods, and phenols were analyzed by high-performance liquid chromatography with diode-array detection (HPLC-DAD), while the concentrations of free and bound volatile aroma compounds were obtained after solid-phase extraction (SPE) followed by gas chromatography–mass spectrometry (GC-MS). Bentonite and tannins in fermentation generally reduced the total dose of bentonite needed for complete stabilization. Treatments with bentonite slightly decreased the concentration of total dry extract, while tannins preserved total acidity. The negative effect of bentonite on flavonoids was more severe. Tannins in fermentation preserved more hydroxycinnamoyltartaric acids with respect to control wine, and this effect was additionally enhanced by bentonite. Volatile and bound aroma composition was affected by all the treatments, while the addition of tannins resulted in higher concentrations of several important odoriferous esters, such as ethyl hexanoate, ethyl decanoate, and hexyl acetate. Additional fining with bentonite to complete protein stabilization annulled some of the positive effects observed after fermentation. [ABSTRACT FROM AUTHOR]

The majority of chemical compounds that contribute to varietal aroma originate from grape skin. To investigate the differences between volatile aroma compounds when different maceration conditions are applied, a total of six vinification treatments were carried out on Malvazija istarska (Vitis vinifera L.) variety, non-maceration control treatment (C), pre-fermentative two days cryomaceration treatment at 8 °C (CRYO), seven days maceration treatment at 16 °C (M7), 14 days maceration treatment at 16 °C (M14), and prolonged post-fermentative maceration treatments at 16 °C for 21 day (M21) and 42 days (M42). Wines were subjected to GC/MS and sensory analysis. Obtained results showed that prolonged post-fermentative maceration treatments contained the highest concentration of total volatile aroma compounds, precisely monoterpenes, alcohols, and other esters. Contrary, C and CRYO wines resulted in highest concentration of ethyl and acetate esters, and fatty acids. In addition, sensory analysis showed that longer maceration treatment wines (M14, M21, M42) were characterized by more aroma complexity, varietal flowery typicity, pronounced fruitiness, with accentuated dried fruit, moderate honey, and herbal notes. Obtained results can provide valuable information to producers when choosing an appropriate vinification technique based on the desired wine style which may lead to a further diversification of white wine market. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of cluster thinning and severe shoot trimming on berry and wine composition and wine sensory characteristics of Merlot variety, in the context of climate change challenges related to grapevine ripening and the corresponding high alcohol content in wine. In two seasons, two different crop sizes were obtained via cluster thinning and combined in a two-factorial design with severe shoot trimming (SST) and its respective high canopy control (HC). In both seasons, cluster thinning (CT) resulted in higher Brix in grape juice and higher alcohol in wine than full crop size (FC), whereas SST obtained lower values than HC. Total anthocyanins and phenolics in wine were increased by CT, whereas SST had no any significant effect on wine's phenolic content. Several sensory characteristics of wine were positively affected by CT in both seasons, including aroma intensity, wine body and overall wine quality, whereas SST wines were in one season characterized by increased perception of vegetal aroma, acidity and bitterness, and decreased perception of body, persistency and taste balance. Our results demonstrate that practices which affect the leaf area to fruit ratio have a major impact on wine sensorial characteristics, concluding that their choice should be based on the desired wine style. [ABSTRACT FROM AUTHOR]

The purpose of the survey was to identify and analyze moderate wine consumption of Croatian autochthonous wine varieties. The survey was conducted in 2019 and 2020 on the Croatian Science Foundation scientific project "Vinum Sanum". Dimensions of wine and health benefits, wine quality, labelling, positive and negative effects on wine labels and psychological well-being were assessed with a questionnaire from 374 participants. Results indicated that wine was perceived as a healthy beverage, consumed as part of healthy life style. Health benefits were perceived positively through cardiac, physical health and psychological well-being. Most important quality features were: origin; micro region, terroir, PGI/PDO (protected geographic origin/protected designation of origin), vintage, ageing and sugar content. This survey might be used as scientific evidence for developing health claims for wine, for producers to use health enhancing properties of wines and create packages and/or labels which may boost the positive perception of wine health benefits. [ABSTRACT FROM AUTHOR]

Viticulture production is challenged by climate change and the consequent higher accumulation of carbohydrates in grapevine berries, resulting in high-alcoholic wines. This study investigates the application of severe shoot trimming performed at three different stages and crop size management as tools for the modulation of cv. Merlot berry composition, aimed at reducing the sugar content in the berry. In the first study, the effects of severe shoot trimming carried out at three different phenological stages were studied. In the second study, late severe shoot trimming was combined with two crop sizes and regulated by shoot thinning. The obtained results demonstrated that severe shoot trimming in earlier stages of berry development limited the accumulation of both sugars and anthocyanins as compared to the control treatment. However, when severe shoot trimming was performed at late veraison (at approximately 14 Brix), it decreased only the accumulation of sugars, without affecting the accumulation of anthocyanins. The results of the second study showed that the modification of crop size by shoot thinning significantly affected the measured yield parameters, whereas the effect on Brix and anthocyanins was seasonally dependent. It was concluded that among the studied techniques, severe shoot trimming at late veraison is the most effective way to reduce sugar content in the berry without affecting the accumulation of anthocyanins. [ABSTRACT FROM AUTHOR]

Pesticide residues and heavy metal concentrations were determined in two depths (0–20 and 20–40 cm) of Chromic Cambisol in 69 vineyards in the Slovenian winegrowing region of the Karst. Similarly, pesticide residues and heavy metal concentrations were also determined in two depths of Calcaric Cambisol in 11 vineyards in the other Slovenian and Croatian winegrowing regions of Istria. The topsoil (0–20 cm) was analysed for the presence of 176 different pesticidal active substances using two multiresidue analytical methods: (a) gas chromatography coupled with mass spectrometry (GC/MS) and (b) liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). Seven active substances (five fungicides and two insecticides) were detected in the soil samples. Their concentrations were compared with the maximum concentrations observed in the vineyards of the winegrowing regions of France, Italy, and Spain. In addition to pesticides, the soil samples were analysed for the presence of nine heavy metals commonly detected in vineyard soils. The concentrations of arsenic, cadmium, cobalt, chromium, copper, molybdenum, nickel, lead, and zinc were below the critical thresholds set by Slovenian legislation, with the exception of one soil sample in which the Cu concentration exceeded the critical threshold. Compared with the maximum concentrations measured in other vineyard soils in Spain, Italy, and France, the heavy metal concentrations in the vineyard soils of Karst and Istria were lower. Both the heavy metal concentrations and the residual concentrations of pesticidal active substances in the vineyard soils of the Karst and Istria regions were significantly lower than the concentrations that are occasionally discussed in the literature. [ABSTRACT FROM AUTHOR]

There is a lack of studies evaluating the metabolic contribution of non-Saccharomyces yeasts in early fermentation phases. This study aimed to investigate the volatile aroma profiles produced by various non-Saccharomyces yeasts just before sequential inoculation with Saccharomyces cerevisiae to provide an insight into the particular effects they induce at this stage. The grape must of Malvazija istarska was inoculated with monocultures of Torulaspora delbrueckii, Metschnikowia pulcherrima, Pichia kluyveri, Lachancea thermotolerans, and Schizosaccharomyces pombe, alongside a S. cerevisiae control. Eighty volatile compounds were quantified via headspace solid-phase microextraction and gas chromatography–mass spectrometry, and the data were statistically elaborated. Volatile profiles of non-Saccharomyces yeasts differed significantly from the S. cerevisiae control. Most treatments caused increases in linalool and β-damascenone, decreases in higher alcohols and fatty acids, and improved synthesis of odoriferous esters. Torulaspora delbrueckii and M. pulcherrima produced compounds not commonly found in S. cerevisiae fermented wines. Multivariate statistical analysis linked the investigated yeasts to specific, particularly abundant compounds. Future studies should explore to what degree these contributions persist after sequential inoculation with S. cerevisiae in diverse grape must matrices. [ABSTRACT FROM AUTHOR]

Moderate wine consumption is often associated with healthy lifestyle habits. The role of wine as a healthy drink is mainly due to its bioactive compounds, which differ according to various viticultural and enological factors. The aim of the present study was to observe the differences in bioactive compounds of white and red autochthonous Croatian wines, differing in terms of the grape variety and production technology. Our further aim was to explore the effect of their moderate consumption (200 mL per day) over the course of six weeks on some aspects of health in sixty-six healthy individuals. Participants were divided into eight groups depending on the wines consumed, while one group formed a non-consuming control group. Medical examination and laboratory tests were performed before the start and at the end of the consumption period. Systolic and diastolic blood pressure, total cholesterol, and LDL concentrations decreased. Additionally, an increase in HDL concentrations, and serotonin and dopamine levels, was observed. ALT, ALP, and GGT levels did not significantly increase in consumer groups, although alcohol concentration was relatively high in all the wines. Such results support the beneficial effects of wine-derived bioactive compounds on some health aspects resulting from moderate white and red wine consumption. [ABSTRACT FROM AUTHOR]

Sauerkraut is produced by cabbage fermentation either spontaneously or by adding lactic acid bacteria. Although commercial cabbage cultivars are more desirable due to their higher yield and uniformity, traditional cultivars are highly prized for their unique sensory characteristics and suitability for fermentation. The aim of this study was to investigate the properties of sauerkrauts from traditional cabbage cultivars ('Brgujski' and 'Žminjski') compared to commercial samples, and to unravel the effects of ambient (18 °C) and cold storage (4 °C) on sauerkraut properties. Higher total phenolic contents and total antioxidant capacities measured by both FRAP and DPPH methods were observed for sauerkrauts from traditional cultivars. In total, 32 volatile compounds were identified, and differences in the volatile profile were observed among the investigated sauerkrauts. The sensory properties of traditional cabbage cultivars were on par, or even better, compared to those of commercially available sauerkraut products. The cold storage conditions characteristic of commercial environments preserved the total antioxidant capacity, the red to green color ratio (a), as well as the lightness (L) of sauerkraut compared to the ambient temperatures characteristic of domestic conditions, indicating the preservation of bioactive compounds responsible for the purple cabbage head coloration of the investigated traditional cultivars. [ABSTRACT FROM AUTHOR]

Highlights • Bentonite fining during fermentation reduced the required dose up to 21%. • The most effective was fining in the middle and at the end of fermentation. • Wines fermented with bentonite had more hydroxycinnamoyltartaric acids than control. • The effect on varietal aromas was weak to moderate. • Bentonite in fermentation preserved key esters and enhanced wine sensory quality. Abstract To test the effects of bentonite addition at various stages of fermentation, five Malvazija istarska white grape must vinification treatments were performed with 100 g/hL of bentonite added in clear juice, at the beginning, in the middle, and at the end of fermentation, while control was fermented without bentonite. Phenols and free and bound volatile aromas were determined by HPLC-DAD and SPE-GC-MS. Wines were evaluated sensorially. Fining during fermentation reduced the total bentonite dose required, and was most effective near the end of fermentation with the reduction of 16% and 21%, depending on the protein stability test. All treated wines preserved more hydroxycinnamoyltartaric acids with respect to control. The side-effect of these treatments on varietal aromas was moderate, but enhanced the preservation of key fermentation volatiles in relation to control, and exhibited positive sensory effects. It was concluded that bentonite added during fermentation may positively affect wine quantity and quality. [ABSTRACT FROM AUTHOR]

BACKGROUND: Leaf removal is a viticultural practice that promotes the biosynthesis of several important grape constituents by improving fruit zone microclimate. The purpose of this study was to assess the effects of hand and mechanical leaf removal, applied at the pea‐size stage of berry development, on fruit zone microclimate, volatile aroma compounds, hydroxycinnamates and sensory characteristics of Istrian Malvasia (Vitis vinifera L.) wines. Three different sunlight exposure conditions were applied: hand leaf removal (HLR), mechanical leaf removal (MLR) and untreated control (UC). RESULTS: Both leaf removal treatments, and especially the more intense HLR, significantly increased the concentration of varietal thiol 3‐sulfanylhexan‐1‐ol, monoterpenes, β‐damascenone and esters. The higher concentration of these aromas contributed to the improvement of wine sensory quality, as expressed by more enhanced floral, fruity and tropical sensory attributes in leaf removal treatments. Hydroxycinnamates were increased only by HLR, a treatment with a greater degree of fruit exposure to sunlight than MLR. CONCLUSION: Leaf removal applied at the pea‐size stage of berry development in a season characterized by abundant rainfall improves both the chemical composition and sensory quality of Istrian Malvasia wine, even when performed by machine, implying that this technique might be successfully applied in large‐scale viticultural production. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Monitorting of plant protection product residues was performed in 12 grape and 66 wine samples of “Malvasia Istriana” variety, produced in Istria winegrowing region of Croatia and Slovenia. The samples were analysed for the presence of 169 different active compounds using two multiresidual analytical methods: gas chromatography coupled with mass spectrometry and liquid chromatography coupled with tandem mass spectrometry. Residues were found in 58.3% of all the inspected grape samples and in 28.8% of all the inspected wine samples. Beside that contents of residues in grapes were below 10% of maximum residue level values and they should not represent any risk for “Malvasia Istriana” grape or wine consumers. [ABSTRACT FROM AUTHOR]

To investigate the changes in physico-chemical and aroma composition after late and ice harvest, Gewürztraminer wines were subjected to standard, enzymatic and GC/MS analysis. Late harvest (LHGW) and ice wines (IHGW) contained more sugars, extract and volatile acidity than standard wines (SGW). IHGW had elevated glycerol and gluconic acid amounts. LHGW was richer in monoterpenol oxides, β-damascenone, 1-octen-3-ol, acetates, ethyl cinnamate and 4-vinylguaiacol than SGW. IHGW contained even higher amounts, with increased citronellol, acetaldehyde, ethyl acetate, dicarboxylic acids esters, benzenoids, furans and acetals, and reduced fermentation aroma compounds. Based on odour activity values, the strongest odorants in SGW were fruity esters. In LHGW the impact of esters increased, while in IHGW cis -rose oxide, β-damascenone and 1,1-diethoxyethane emerged as the most potent. Fruity and sweet were the dominant aroma compound series in SGW and LHGW, but in IHGW declined, while terpenic, floral, chemical, pungent and ripe fruit aroma compound series increased. [ABSTRACT FROM AUTHOR]

To investigate possible relationships, the volatile aroma compound composition of 30 grape marc distillates obtained from six varieties was correlated with the sensory scores for basic properties ( clearness, odour and taste) obtained by sensory testing using the hedonic German DLG model. High negative Pearson's correlation coefficients were determined between total concentrations of long-chain ethyl esters and the scores for the property clearness. Strong positive correlation of middle-chain fatty acids and their ethyl esters, and strong negative correlation of sesquiterpenes, diterpenes, methanol, C6-alcohols, acetic and short-chain fatty acids, long-chain ethyl esters, ethyl acetate, other acetate esters, acetaldehyde and furanic compounds with the properties odour and taste were found. Principal component analysis corroborated these results. Monoterpenes were confirmed to be responsible for a typical Muscat aroma, as well as for descriptors such as flowery, rose, citrus and spicy/menthol in distillates made from Muscat varieties. A significant degree of correlation was found between the concentration of C6-alcohols and the frequency of quotation of the descriptor vegetative/grass. Indications were found that vegetative odours of C6-alcohols may act as suppressants of Muscat aroma. A certain degree of congruence was noted between higher concentrations of medium-chain ethyl esters and acetaldehyde, and the occurrence of fruity and nutty odours, respectively. Copyright © 2012 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The influence of different grape mash maceration treatments on the varietal and secondary aroma profiles of wines produced from an aromatic red grape variety, Mugkat ruža porečki, have been investigated. Two essentially different tectmiques were applied, fermentative maceration at room temperature and prefermentative cryomaceration, both in durations of one, three and five days. Generally, higher concentrations of free and bound varietal aroma compounds were found in wines obtained by maceration at room temperature in relation to cryomaceration. Regarding the effect of the duration of maceration, the highest concentrations were determined in wines obtained by three-day maceration treatments, in both fermentative and cryomaceration treatments. Secondary aroma compounds followed a less uniform pattern. The compounds with the highest odour unit values in all investigated wines were linalool, citronellol, geraniol, β-damascenone, β-ionone, isoamyl alcohol, 2-phenylethanol, ethyl hexanoate, ethyl octanoate, isoamyl acetate, ethyl acetate, and diethyl succinate. It has been shown that Muškat ruža porečki is an aromatic variety, producing wines with notable monoterpenol fraction, which are characterized by a typical varietal Muscat aroma with a dominant rose odour accompanied by red fruit nuances. Sensorially, longer maceration treatments improved odour and overall wine quality, together with the intensity and recognisability of varietal Muscat aroma, while short-term cryomaceration emerged as a preferable technique for the production of light rosé wines with pronounced Muscat aroma and low phenolic content. The presented maceration techniques were shown to be applicable for the production of different types of Muškat ruža porečki rosé and red wines. [ABSTRACT FROM AUTHOR]

To investigate the behaviour of volatile compounds during a traditional alembic distillation, large numbers of important volatile compounds were identified and quantified by GC/MS and GC/FID analysis in different fractions of grape marc distillates made from two Muscat varieties. Generally, concentrations of terpenes, C13-norisoprenoids, acids and particular waxy esters and aldehydes were found to increase, while concentrations of higher alcohols and the majority of fruity and flowery esters were found to decrease during distillation. Because of the abundance in odoriferous monoterpenes, utilization of the tail fraction as a raw material for re-distillation was considered appropriate. [ABSTRACT FROM AUTHOR]

In order to investigate the composition of secondary aroma compounds of fresh grape marc distillates as a result of variety and production technology, 30 samples (6 varietiesx5 samples) were analysed. White grape marc samples from Malvazija istarska, Chardonnay and Muscat Blanc were obtained as by-products in standard white wine production, while red grape marc samples from Teran and Cabernet Sauvignon were obtained after standard red wine production procedures. Marc from red grape variety Muškat ruža porečki was obtained during the production of rose wines. All fermented marc samples were distilled using a traditional copper alembic. The obtained distillates were subjected to GC/MS and GC/FID analyses. Malvazija istarska distillates exhibited exceptionally high methanol content. Distillates from white grape varieties were found to be characterized by higher C, alcohol and I-propanol concentrations, while red grape distillates contained higher amounts of the majority of alcohols, acids, and esters. In Mužkat ruža distillates intermediate concentrations of many important aroma compounds were found. It was concluded that differences in the production technology parameters, depending on the variety, resulted in differences in secondary aroma profiles, most evident between distillates from white and red varieties. These findings were confirmed applying stepwise linear discriminant analysis (SLDA), which resulted in 100 % correct classification of distillates according to the variety and corresponding production technology. [ABSTRACT FROM AUTHOR]

In order to investigate the relationship between sensory and gas chromatographic analysis data, and to establish if particular aroma compounds could be used as Malvazija istarska young wine quality markers, 30 samples of Malvazija istarska young wine were subjected to sensory evaluation and gas chromatographic analysis of aroma compounds. Linear regression and principal component analysis were applied in order to establish the relations between sensory evaluation scores and aroma compound concentrations in corresponding wines. The most important contributors to the characterization and differentiation of wines evaluated with higher sensory evaluation scores were isoamyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, hexanoic acid, octanoic acid and decanoic acid. On the other hand, wines evaluated with lower sensory evaluation scores were characterized and differentiated by higher amounts of isoamyl alcohol and isobutanol. Mentioned esters and acids were also found to be the most important variables for the classification of these wines according to quality using stepwise linear discriminant analysis (SLDA). The evaluation of the SLDA model was performed by cross-validation, obtaining an average percentage of correct classification of 100.0%, and of correct prediction of 89.3%. The results of this investigation suggest that above-mentioned esters, acids and alcohols could be used as markers of Malvazija istarska young wine quality. PRACTICAL APPLICATIONS Wine aroma is one of the most important parameters responsible for its quality, and hence for consumer acceptance. Sensory evaluation is the most common technique for controlling the organoleptic quality of wine, but it is not always feasible, since it requires specific conditions, and a group of trained expert tasters that can only assess a relatively small number of wine samples for a day. Moreover, the subjectivity of panelists can affect the evaluation in a great measure. The approach proposed in this work suggests the use of a nonsubjective instrumental technique such as gas chromatography for the analysis of volatile aroma compounds as a complementary tool for wine quality control able to predict, confirm or to correct the results of Malvazija istarska young wine sensory evaluation. Although this model is yet far from being practically implemented, information obtained could be used as a starting ground. Moreover, it was assumed that the approach proposed in this work is likely to be applied successfully on the differentiation and classification of other types of wine according to quality. [ABSTRACT FROM AUTHOR]

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• UPLC-QqQ-MS/MS profiling of 58 phenols in 173 wines, 4 red and 6 white grape varieties. • Many phenols as varietal markers, efficacy of differentiation by SLDA >95% in all cases. • Potent differentiators: peonidin 3-(6″-acetyl)-glucoside and taxifolin for red, cis -piceid for white wines. • Anthocyanin composition was useful for elucidating diverse typical colour attributes. • trans -fertaric acid, isorhapontin, phlorizin, quercetin 3-rhamnoside, myricitrin were typical for Plavac mali red wine. Targeted ultra-performance liquid chromatography with triple quadrupole mass spectrometric (UPLC-QqQ-MS/MS) profiling of phenolic compounds was utilised for varietal differentiation of 173 wines made from four red and six white grape varieties. Among 58 identified phenols many were found relevant as exclusive or partial discriminators between wines. Successful differentiation models were built by linear discriminant analysis with the percentage of correct classification higher than 95% in all cases, with peonidin 3-(6″-acetyl)-glucoside and taxifolin as the most potent differentiators between red, and cis -piceid between white monovarietal wines. Diverse typical colour attributes among the monovarietal wines were tentatively ascribed to the variations in the composition of monomeric anthocyanins. Plavac mali red wine exhibited the most specific composition, and its most typical samples were distinguished by the abundance in trans -fertaric acid, isorhapontin, phlorizin, quercetin 3-rhamnoside, and myricitrin. Despite positive correlations with particular astringent flavonols, the typical astringency of Plavac mali wine remained unresolved. [ABSTRACT FROM AUTHOR]

To investigate the changes in wine chemical composition, sensory quality, and style induced by various levels of skin disruption and contact with oxygen during grape processing, five treatments were applied: whole grape cluster pressing in semi‐reductive conditions (WCP‐R), whole grape cluster pressing in standard conditions (WCP), standard grape mash pressing as a control (GMP), light (LOX), and heavy oxidation of grape juice (HOX). Produced wines were subjected to analysis of phenols (HPLC‐DAD) and volatiles (HS‐SPME‐GC/MS), as well as quantitative descriptive sensory analysis. WCP‐R wines stood out with the highest amounts of hydroxycinnamates and preserved aromas, and the highest intensities of positive sensory attributes. Both WCP and LOX treatments significantly reduced phenols when compared to GMP, while HOX treatment was detrimental in general. Apparently, the level of contact with oxygen exhibited a predominant effect on hydroxycinammates and aromas, while the level of grape skin disruption affected primarily hydroxybenzoic acids and flavan‐3‐ols. Practical applications: This study has demonstrated that by choosing grape processing techniques which are different from respect to degree of skin cell disruption and contact with juice, as well as contact with oxygen, it is possible to obtain a variety of white wine styles differing in the content and composition of phenols and volatile aromas, which significantly reflect on their sensory quality. This could be of particular interest for grape varieties with deficient or excessive phenol and aroma potentials, which have to be specifically processed to achieve a satisfactory balance within a desired wine style. Besides deepening the existing and providing new knowledge on the broad topic of grape processing in winemaking, the results obtained are characterized by high level of transferability to wine industry. They may serve experts and producers to draw more precise conclusions on the relative effectiveness of different grape processing techniques, and choose adequate options for their specific needs. [ABSTRACT FROM AUTHOR]

To investigate the varietal aroma compound composition of monovarietal grape marc distillates made from six different varieties (Vitis vinifera L.) in the region of Istria (Croatia), 30 samples were subjected to GC/MS and GC/FID analysis. A total of 73 compounds were identified: 45 monoterpenes, 20 sesquiterpenes, 3 diterpenes, and 5 C(13)-norisoprenoids. The largest number and the highest concentration of monoterpenes were found in Muscat Blanc, followed by Rose Muscat of Porec (Muskat ruza porecki) distillates, which were both characterized as highly aromatic. Lower, but still significant monoterpenol content was determined in distillates made from Istrian Malvasia (Malvazija istarska) grape marc. Chardonnay, Cabernet Sauvignon, and Teran distillates exhibited poorer monoterpene profiles, while Teran distillates contained elevated sesquiterpene concentrations. It was concluded that investigated monovarietal grape marc distillates significantly differ in varietal aroma compound composition. Stepwise linear discriminant analysis provided efficient discrimination models, and extracted various monoterpenes, sesquiterpenes and C(13)-norisoprenoids as important differentiators of distillates according to varietal origin.