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1.
Molecules ; 29(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38202600

RESUMO

Selective enhancement of wine aroma was achieved using a broad spectrum of exogenous glycosidases. Eight different enzyme preparations were added to Verdejo wine, resulting in an increase in the levels of varietal volatile compounds compared to the control wine after 15 days of treatment. The enzyme preparations studied were robust under winemaking conditions (sulfur dioxide, reducing sugars, and alcohol content), and no inhibition of ß-glucosidase activity was observed. Significant differences were detected in four individual terpenes (α-terpineol, terpinen-4-ol, α-pinene, and citronellal) and benzyl alcohol in all the treated wines compared to the control wine, contributing to the final wine to varying degrees. In addition, a significant increase in the other aromatic compounds was observed, which showed different patterns depending on the enzyme preparation that was tested. The principal component analysis of the data revealed the possibility of modulating the different aromatic profiles of the final wines depending on the enzyme preparation used. Taking these results into account, enhancement of the floral, balsamic, and/or fruity notes of wines is possible by using a suitable commercial enzyme preparation.


Assuntos
Glicosídeos Cardíacos , Vinho , Glicosídeos , Hidrólise , Odorantes , Glicosídeo Hidrolases
2.
J Sci Food Agric ; 103(7): 3613-3620, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36208475

RESUMO

BACKGROUND: High-power ultrasound is a novel and non-thermal technique normally used in red vinification to increase the extraction of phenolic compounds. However, few studies have been carried out on its effect on the extraction of aroma compounds and their precursors in white grapes. This study evaluates the effect of high-power ultrasound at winery scale in the maceration of Viognier grapes on the content of varietal volatile compounds (free and glycosidically bound) in musts and wines, in comparison with wines from direct pressing and from short skin maceration. RESULTS: The pre-fermentative ultrasound treatment of the grapes produced an increase in most of the varietal compounds of musts and wines, both in the free fraction and in the bound one, especially in the C6 alcohols, terpenes and norisoprenoids, some of them of sensory relevance, while the effect on esters and lactones was less evident. Ultrasound maceration allowed us to obtain wines of higher aromatic intensity, with a more pronounced varietal character. CONCLUSION: The pre-fermentative ultrasound treatment of Viognier grapes increases the aromatic potential of the wines, as it favors the extraction of free and bound varietal volatile compounds. In addition, it allows the maceration time of the grapes to be reduced compared to conventional pre-fermentation techniques, thus avoiding oxidative processes that could negatively affect the aroma of the wines. © 2022 Society of Chemical Industry.


Assuntos
Vitis , Compostos Orgânicos Voláteis , Vinho , Álcoois/análise , Odorantes/análise , Terpenos/análise , Vitis/química , Compostos Orgânicos Voláteis/análise , Vinho/análise , Ultrassom
3.
Yale J Biol Med ; 96(2): 205-210, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37396975

RESUMO

Climate change and environmental health are closely linked with agriculture and food supply. The environment influences accessibility, quality, and variety of foods and drinks that are available for consumption, which in turn influences population health. A growing area of research is the role of dietary intake of nutrients and how they may influence risk for skin cancer. In recent years, our group has studied dietary nutrients, particularly those found in commonly consumed beverages, such as those containing caffeine, citrus products, and alcohol, in large prospective cohorts to evaluate how their intake may influence risk for skin cancer. Our data suggest that intake of citrus juices, when consumed around once per day or more, or around 5 to 6 times per week, may be associated with increased risk for both keratinocyte carcinomas (KC) and malignant melanoma (MM). With regards to alcohol consumption, we have found that intake of white wine may be associated with increased risk for both KC and MM, while beer and red wine have not shown such associations. Lastly, our work suggests caffeinated beverages, including coffee, tea, and cola, may be associated with decreased risk for basal cell carcinoma (BCC) and MM. While the associations between food intake and skin cancer development are complex, and remain to be further analyzed in future studies, we hope that our summary may help guide individuals to small changes they may make towards potentially reducing their risk for certain skin cancers.


Assuntos
Citrus , Neoplasias Cutâneas , Café/efeitos adversos , Estudos Prospectivos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Etanol , Melanoma Maligno Cutâneo
4.
J Appl Microbiol ; 133(2): 656-664, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35451085

RESUMO

AIM: We aim to explore the non-structural sugars from white wine grape pomace (WWGP) as the input carbon source for the co-production of multiple high-value products by the non-fastidious yeast Rhodotorula babjevae to create a sustainable and economically appealing process. METHODS AND RESULTS: Water extraction of unfermented, soluble sugars from WWGP yielded extracts with similar amounts of glucose and fructose, which were used to prepare a growth medium. Rhodorotula babjevae multiplied as fast on WWGP-based medium as on a reference medium but achieved higher cell dry weight (CDW) and lower intracellular triacylglycerol accumulation (22.5% vs. 28.6%) in WWGP-based medium. In addition, R. babjevae produced mannitol and arabitol and carotenoids and secreted polyol esters of fatty acids, a rare type of glycolipid as confirmed by Fourier transform-infrared, nuclear magnetic resonance and high-performance liquid chromatography analyses. Remarkably, R. babjevae consumed simultaneously both fructose and glucose when on WWGP-based medium and left glucose practically untouched in the reference medium, evidencing a fructophilic character. CONCLUSIONS: Rhodorotula babjevae, a metabolic versatile yeast, proliferated on a minimally processed extract and successfully converted glucose and fructose into high-value products. SIGNIFICANCE AND IMPACT OF STUDY: Different chemicals with market potential can be produced through the valorization of abundant waste feedstocks generated by the wine industry to which R. babjevae can contribute.


Assuntos
Vitis , Carbono , Carotenoides , Ácidos Graxos/metabolismo , Frutose , Glucose/metabolismo , Açúcares , Leveduras/metabolismo
5.
Molecules ; 27(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35011556

RESUMO

The oxidation processes of white wines can occur during storage and commercialization due to several factors, and these can negatively affect the color, aroma, and quality of the wine. Wineries should have faster and simpler methods that provide valuable information on oxidation stability of wines and allow fast decision-making procedures, able to trigger suitable technological interventions. Using a portable prototype instrument for light irradiations at different wavelengths and times was considered and evaluated on sensorial, spectrophotometric, and colorimetric parameters of white wines. The sensorial analysis revealed that white and light blue were the most significant, after only 1 h of irradiation. The experimental results showed that hydrogen peroxide could enhance the effect of light treatment, allowing a contemporary evaluation of the oxidation stability of wine against light and chemical stresses. As expected, a good correlation (R2 > 0.89) between optical density at 420 nm and b* parameter was highlighted. The synergic effect of light and H2O2 was also studied on the hydrolyzable and condensed tannins' additions to white wine. The proposed methodology could be used to evaluate the oxidative stability of white wines, but also to evaluate the effect of some oenological adjuvants on wine stability.


Assuntos
Luz , Oxirredução/efeitos da radiação , Vinho/análise , Vinho/efeitos da radiação , Análise de Alimentos , Peróxido de Hidrogênio/análise , Estresse Oxidativo , Compostos Orgânicos Voláteis
6.
Molecules ; 27(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35164074

RESUMO

Clarification of the musts is carried out to remove particles that cause turbidity, oxidizable polyphenols, and eliminate excess of proteins. However, an excessive clarification of the musts can lead to the reduction of volatile compound concentrations and, as a consequence, modify the sensorial properties of the wines. Therefore, in this study, the influence of two pre-fermentation clarification techniques (static settling and flotation) on the concentrations of volatile compounds has been assessed in Albariño and Treixadura wines. Fermentations were performed at an industrial scale. Volatile compounds have been identified and quantified by gas chromatography (FID and mass spectrometry detection) and expert panelists assessed the sensory properties of the final wines. The results showed effects of the clarification techniques on the volatile composition of wines from both varieties. Flotation significantly increased the concentrations of benzyl alcohol in Treixadura wines, whereas this technique increased the concentration of 1-hexanol, octanoic acid, and furfural in Albariño wines, but without exceeding the corresponding perception thresholds. Panelists tended to score higher the wines coming from flotation, which, together with the shorter application time, makes this technique suitable for clarifying the musts of these two white varieties.

7.
Molecules ; 27(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35011467

RESUMO

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.


Assuntos
Análise de Alimentos , Oxirredução , Paladar , Vinho/análise , Flavonoides/análise , Flavonoides/química , Análise de Alimentos/métodos , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Polifenóis/análise , Polifenóis/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
8.
Molecules ; 26(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34500729

RESUMO

Light exposure of white wine can cause a light-struck taste (LST), a fault induced by riboflavin (RF) and methionine (Met) leading to the formation of volatile sulfur compounds (VSCs), including methanethiol (MeSH) and dimethyl disulfide (DMDS). The study aimed to investigate the impact of different antioxidants, i.e., sulfur dioxide (SO2), glutathione (GSH) and chestnut tannins (CT), on preventing LST in model wine (MW) and white wine (WW), both containing RF and Met. Both MW and WW samples were added with the antioxidants, either individually or in different combinations, prior to 2-h light exposure and they were stored in the dark for 24 months. As expected, the light induced the degradation of RF in all the conditions assayed. Met also decreased depending on the antioxidants added. The presence of antioxidants limited the formation of LST as lower concentrations of VSCs were found in both MW and WW samples. In the latter matrix, neither MeSH nor DMDS were detected in the presence of CT, while only DMDS was found in WW+GSH, WW+SO2+GSH and WW+CT+SO2 samples at a concentration lower than the perception thresholds. Considering the antioxidants individually, the order of their effectiveness was CT ≥ GSH > SO2 in WW under the adopted experimental conditions. The results indicate tannins as an effective enological tool for preventing LST in white wine and their use will be further investigated in different white wines under industrial scale.


Assuntos
Glutationa/química , Taninos Hidrolisáveis/química , Luz , Dióxido de Enxofre/química , Vinho
9.
Molecules ; 26(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299536

RESUMO

The volatile thiol compound 3-sulfanylhexan-1-ol (3SH) is a key impact odorant of white wines such as Sauvignon Blanc. 3SH is produced during fermentation by metabolism of non-volatile precursors such as 3-S-gluthathionylhexanal (glut-3SH-al). The biogenesis of 3SH is not fully understood, and the role of glut-3SH-al in this pathway is yet to be elucidated. The aldehyde functional group of glut-3SH-al is known to make this compound more reactive than other precursors to 3SH, and we are reporting for the first time that glut-3SH-al can exist in both keto and enol forms in aqueous solutions. At wine typical pH (~3.5), glut-3SH-al exists predominantly as the enol form. The dominance of the enol form over the keto form has implications in terms of potential consumption/conversion of glut-3SH-al by previously unidentified pathways. Therefore, this work will aid in the further elucidation of the role of glut-3SH-al towards 3SH formation in wine, with significant implications for the study and analysis of analogous compounds.


Assuntos
Compostos de Enxofre/metabolismo , Aldeídos/metabolismo , Fermentação/fisiologia , Hexanóis/metabolismo , Odorantes/análise , Compostos de Sulfidrila/metabolismo , Vitis/metabolismo , Vinho/análise
10.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684769

RESUMO

Protein haze in white wine is one of the most common non-microbial defects of commercial wines, with bentonite being the main solution utilized by the winemaking industry to tackle this problem. Bentonite presents some serious disadvantages, and several alternatives have been proposed. Here, an alternative based on a new cellulose derivative (dicarboxymethyl cellulose, DCMC) is proposed. To determine the efficiency of DCMC as a bentonite alternative, three monovarietal wines were characterized, and their protein instability and content determined by a heat stability test (HST) and the Bradford method, respectively. The wines were treated with DCMC to achieve stable wines, as shown by the HST, and the efficacy of the treatments was assessed by determining, before and after treatment, the wine content in protein, phenolic compounds, sodium, calcium, and volatile organic compounds (VOCs) as well as the wine pH. DCMC applied at dosages such as those commonly employed for bentonite was able to reduce the protein content in all tested wines and to stabilize all but the Moscatel de Setúbal varietal wine. In general, DCMC was shown to induce lower changes in the wine pH and phenolic content than bentonite, reducing the wine calcium content. Regarding which VOCs are concerned, DCMC produced a general impact similar to that of bentonite, with differences depending on wine variety. The results obtained suggest that DCMC can be a sustainable alternative to bentonite in protein white wine stabilization.


Assuntos
Bentonita/química , Carboximetilcelulose Sódica/química , Vinho/análise , Cálcio/análise , Manipulação de Alimentos , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Fenóis/análise , Proteínas de Plantas/análise , Proteínas de Plantas/química , Estabilidade Proteica , Compostos Orgânicos Voláteis/análise
11.
Molecules ; 26(3)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494502

RESUMO

Recently, the use of alternative vessels to oak barrels during winemaking has become increasingly popular, but little is known about their impact on the chemical composition of the resulting wines. To address this issue, a Sauvignon Blanc wine was elaborated from the same grape juice by using cylindrical stainless-steel tanks, oval-shaped concrete vessels, oval-shaped polyethylene vessels, and clay jars in triplicate. Each vessel was used for alcoholic fermentation and the aging of wines over its own lees. Wines elaborated in concrete vessels showed the highest pH and the lowest titratable acidity, most likely related to the observed release of inorganic compounds from the concrete walls. Little effect of the vessels was seen on the wine color and phenolic composition. Wines elaborated in clay jars showed the highest turbidity and the highest content of soluble polysaccharides, while those made using cylindrical stainless-steel tanks showed the highest content of volatile compounds. Despite the observed differences, all of the vessels tested seem suitable for white wine production since every wine showed chemical features that corresponded with the quality standards of Sauvignon Blanc wines.


Assuntos
Quercus , Compostos Orgânicos Voláteis/análise , Vinho
12.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959818

RESUMO

The DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay is an easy and efficient method commonly used to determine the antioxidant capacity of many food matrices and beverages. In contrast with red wines, white wines are poorer in antioxidant polyphenolics, and the more hydrophilic sulfur-containing compounds in them may contribute significantly to their antioxidant capacity. The modification of the classical DPPH method, with a methanol-buffer and the measure of EC20 (quantity of sample needed to decrease the initial DPPH concentration by 20%) has shown that sulfur-containing compounds such as cysteine (0.037 ± 0.003), glutathione (0.054 ± 0.003) or methanethiol (0.104 ± 0.003) appeared to bear antioxidant capacity comparable to well known phenolic compounds, such as catechin (0.035 ± 0.003), caffeic acid (0.057 ± 0.003) and ferulic acid (0.108 ± 0.003), respectively. In the case of white wines, the comparison with REDOX-sensory scores showed that results from this modified DPPH assay are strongly correlated with sensory attributes (r = 0.73, p < 0.1). These results provide an unprecedented illustration of the important contribution of these sulfur-containing compounds to the radical quenching ability of white wines.


Assuntos
Antioxidantes/química , Compostos de Bifenilo/química , Ensaios de Triagem em Larga Escala/métodos , Picratos/química , Vinho/análise , Ácidos Cafeicos/química , Catequina/química , Ácidos Cumáricos/química , Humanos , Fenóis/química , Compostos de Enxofre/química
13.
Crit Rev Food Sci Nutr ; 58(17): 2939-2956, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28678530

RESUMO

White wine mouthfeel which encompasses the tactile, chemosensory and taste attributes of perceived viscosity, astringency, hotness and bitterness is increasingly being recognized as an important component of overall white wine quality. This review summarizes the physiological basis for the perception of white wine mouthfeel and the direct and interactive effects of white wine composition, specifically those of low molecular weight phenolic compounds, polysaccharides, pH, ethanol, glycerol, dissolved carbon dioxide, and peptides. Ethyl alcohol concentration and pH play a direct role in determining most aspects of mouthfeel perception, and provide an overall framework on which the other minor wine components can interact to influence white wine mouthfeel. Phenolic compounds broadly impact on the mouthfeel by contributing to its viscosity, astringency, hotness and bitterness. Their breadth of influence likely results from their structural diversity which would allow them to activate multiple sensory mechanisms involved in mouthfeel perception. Conversely, polysaccharides have a small modulating effect on astringency and hotness perception, and glycerol does not affect perceived viscosity within the narrow concentration range found in white wine. Many of the major sensory attributes that contribute to the overall impression of mouthfeel are elicited by more than one class compound suggesting that different physiological mechanisms may be involved in the construct of mouthfeel percepts.


Assuntos
Sensação , Vinho , Etanol , Humanos , Concentração de Íons de Hidrogênio , Paladar
14.
Anal Bioanal Chem ; 410(15): 3483-3490, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29256073

RESUMO

A UHPLC-MS/MS method was developed for the quantification of the main compounds involved in oxidation reactions occurring in white musts and wines such as hydroxycinnamic acids, their glutathione and cysteinylglycine adducts (GRP, GRP2, 5-(S-glutathionyl)-trans-caftaric acid, 2-(S-cysteinylglycyl)-trans-caftaric acid, and 2-(S-glutathionyl)-trans-caffeic acid), and reduced and oxidized glutathione (GSH, GSSG) in wine. Since oxidation is the main concern in white wine-making, directly affecting its quality, the developed method was then applied in a series of white wines made with different pre-fermentation treatments to limit oxidation at must stage. The glucose esters and/or glucosides of hydroxycinnamic acids were quantified as glucogallin equivalent. The developed method led to an overall improvement in the limits of detection (LODs) and quantification (LOQs) for all the compounds studied in comparison to other methods such as high-performance liquid chromatography with fluorescence detection (HPLC-FLD) or diode array UV detection (HPLC-DAD). LOD values ranged from 0.0002 to 0.0140 mg/L and LOQs from 0.0005 to 0.0470 mg/L. The recoveries ranged between 80 and 110% in wines, and the relative standard deviation (RSD) for precision intra- and inter-day was below 15%. The accuracy and intra- and inter-day precision met the acceptance criteria of the AOAC international norms. As far as we know, this study is the first report of quantification of GRP, 2-(S-cysteinylglycyl)-trans-caftaric acid, and 2-(S-glutathionyl)-trans-caffeic acid using these non-commercially available compounds as external standards. Those compounds represent a significant proportion of hydroxycinnamic acid derivatives in wines. The methodology described is suitable for the analysis of hydroxycinnamic derivatives in wines.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/análise , Espectrometria de Massas em Tandem/métodos , Vinho/análise , Dipeptídeos/análise , Glutationa/análise , Limite de Detecção , Oxirredução , Fenóis/análise , Espectrometria de Massas por Ionização por Electrospray/métodos
15.
Molecules ; 23(6)2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29857507

RESUMO

The aim of the present study was to compare and analyze the impact of using bee pollen doses (0.1, 0.25, 1, 5, 10 and 20 g/L) as activator in the alcoholic fermentation process of Palomino fino and Riesling wines. In this regard, its influence on the musts composition, the fermentative kinetics, the evolution of the populations of Saccharomyces cerevisiae, the evolution of yeast-assimilable nitrogen and physico-chemical characteristics of final wines has been analyzed. Bee pollen addition produces significant increases in yeast-assimilable nitrogen and maximum yeasts population and exponential velocity reached during alcoholic fermentation. Bee pollen showed an important effect on yeast survival during the death phase. Final wines showed significantly increase in volatile acidity above doses higher than 10 g/L and Comisión Internacional de L'Eclairage parameters (CIELab), color intensity and Abs 420 nm, from 1 g/L. Therefore, pollen could be used as fermentative activator for the alcoholic fermentation of white wines applying doses below of 1 g/L.


Assuntos
Abelhas/química , Fermentação , Pólen/química , Saccharomyces cerevisiae/metabolismo , Vitis/química , Vinho , Animais , Biomassa , Fenômenos Químicos , Concentração de Íons de Hidrogênio , Pigmentação
16.
J Sci Food Agric ; 98(9): 3532-3541, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29297926

RESUMO

BACKGROUND: This paper provides data for the potential use of a color chart to establish the best quality of white wine grapes destined for postharvest processing. Grechetto, Vermentino and Muscat of Alexandria white wine grape varieties were tested by sampling berries at different dates during their quality attribute evolution. A color chart and reflectance spectrocolorimeter were used in combination with analyses of total carotenoids and chlorophylls in all three varieties and of volatile organic compounds (VOCs) in Grechetto alone. RESULTS: Total carotenoids decreased from 0.85 to 0.76 µg g-1 in Grechetto berries and from 0.70 to 0.46 µg g-1 in Vermentino berries while increased from 0.70 to 0.80 µg g-1 in Muscat berries during ripening. Total chlorophylls decreased in all varieties, and a strict correlation was found between hue angle (measured by color chart or spectrocolorimeter) and chlorophyll disappearance, with R2 ranging from 0.81 to 0.95 depending on the variety. VOCs were only measured in Grechetto grapes, and a significant increase in glycosylation was found with ripening. The concentration of different classes of VOCs exhibited a clear decrease during ripening, except for terpenoids and esters which showed a peak at the beginning. The benzenoid class reached the highest concentration, which was almost 50% of the total. Cluster analysis using Ward's method enabled the best grape quality to be identified. CONCLUSION: This experimental work highlights that a color chart is cheap and easy to use to define the right quality stage for white wine grapes. The color chart enabled the enochemical features to be matched with the VOC results for the aromatic maturity of Grechetto. © 2018 Society of Chemical Industry.


Assuntos
Cor , Colorimetria/métodos , Frutas/química , Vitis/química , Vinho/análise , Agricultura/métodos , Carotenoides/análise , Clorofila/análise , Colorimetria/instrumentação , Ésteres/análise , Frutas/crescimento & desenvolvimento , Terpenos/análise
17.
World J Microbiol Biotechnol ; 34(11): 161, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30357477

RESUMO

In this study, the effect of sequential inoculation with non-Saccharomyces (Hanseniaspora guilliermondii) and Saccharomyces cerevisiae yeast on the distinctive characteristics of the Campanino white wine was investigated. For this purpose, three independent winemaking experiments were carried out on an industrial scale (batches A, B and C). In detail, the first one was carried out using the sequential inoculation technique while the other two, using a S. cerevisiae single-strain starter or no inoculation representing the control batches. Microbiological and chemical parameters and sensorial profiles of the wines were defined. Interestingly, the results showed that when sequential cultures (H. guilliermondii in a sequential mixture with S. cerevisiae) were used, a better wine aroma and quality was observed. More specifically, the wine obtained by sequential inoculation showed lower acetic acid values and enhanced volatile profiles than the wine from the control batches. Finally, sensorial analysis confirmed that the sequential cultures led to an improvement in wine flavour. Therefore, results suggest that the sequential inoculation using non-Saccharomyces and Saccharomyces yeast represents a biotechnological practice that can improve the quality features of traditional white wine. It has been shown for the first time that on an industrial scale H. guilliermondii could be used in sequential inoculum with S. cerevisiae in making white Campanino wine.


Assuntos
Hanseniaspora/crescimento & desenvolvimento , Microbiologia Industrial/métodos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Vinho/microbiologia , Ácido Acético , Técnicas de Cultura Celular por Lotes , Reatores Biológicos , Meios de Cultura/metabolismo , Fermentação , Hanseniaspora/metabolismo , Cinética , Odorantes , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/análise
18.
J Food Sci Technol ; 55(1): 424-430, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29358836

RESUMO

The aim of this work was to study the effect of different configurations of packaging on the volatile composition and sensory properties of a white wine. Certain oenological parameters were also evaluated. Bag-in-box (BIB) and glass bottles sealed with two different cork stoppers, natural and Neutrocork (technical), were used in the experiments. Analysis were carried out before packaging and after 3, 6 and 12 months of storage. Results showed that wines packaged in BIB presented higher levels of brown color than wines in bottles sealed with corks. In all packaging configurations, the content of free SO2 decreased with storage time; however, BIB wines showed a lower content of free SO2 than bottle wines during 12 months. Moreover, wines under BIB presented a significant lower amount of 2-phenylethanol, 2-phenylethyl acetate, isoamyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, linalool and ß-damascenone than bottled wines.

19.
Anal Bioanal Chem ; 409(10): 2757-2766, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28180990

RESUMO

Two analytical separation methods-size-exclusion chromatography and asymmetrical flow field-flow fractionation-were implemented to evaluate the integrity of the colloidal composition of Chardonnay white wine and the impact of pressing and fermentations on the final macromolecular composition. Wine chromophoric colloidal matter, representing UV-visible-absorbing wine macromolecules, was evaluated by optical and structural measurements combined with the description of elution profiles obtained by both separative techniques. The objective of this study was to apply these two types of fractionation on a typical Chardonnay white wine produced in Burgundy and to evaluate how each of them impacted the determination of the macromolecular chromophoric content of wine. UV-visible and fluorescence measurements of collected fractions were successfully applied. An additional proteomic study revealed that grape and microorganism proteins largely impacted the composition of chromophoric colloidal matter of Chardonnay wines. Asymmetrical flow field-flow fractionation appeared to be more reliable and less invasive with respect to the native chemical environment of chromophoric wine macromolecules, and hence is recommended as a tool to fractionate chromophoric colloidal matter in white wines. Graphical Abstract An innovative macromolecular separation method based on Asymmetrical Flow Field-Flow Fractionation was developed to better control colloidal dynamics across Chardonnay white winemaking.


Assuntos
Coloides/isolamento & purificação , Fracionamento por Campo e Fluxo/métodos , Proteoma/análise , Vinho/análise , Coloides/análise , Coloides/química , Humanos , Proteômica/métodos
20.
Molecules ; 22(8)2017 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-28825618

RESUMO

Xanthylium derivatives are yellow to orange pigments with a glyoxylic acid bridge formed by dimerization of flavanols, which are built by oxidative cleavage of tartaric acid. Although their structure and formation under wine-like conditions are well established, knowledge about their color properties and their occurrence and importance in wine is deficient. Xanthylium cations and their corresponding esters were synthesized in a model wine solution and isolated via high-performance countercurrent chromatography (HPCCC) and solid phase extraction (SPE). A Three-Alternative-Forced-Choice (3-AFC) test was applied to reveal the color perception threshold of the isolated compounds in white wine. Their presence and color impact was assessed in 70 different wines (58 white and 12 rosé wines) by UHPLC-DAD-ESI-MSn and the storage stability in wine was determined. The thresholds in young Riesling wine were 0.57 mg/L (cations), 1.04 mg/L (esters) and 0.67 mg/L (1:1 (w/w) mixture), respectively. The low thresholds suggest a possible impact on white wine color, but concentrations in wines were below the threshold. The stability study showed the degradation of the compounds during storage under several conditions. Despite the low perception threshold, xanthylium derivatives might have no direct impact on white wine color, but might play a role in color formation as intermediate products in polymerization and browning.


Assuntos
Compostos Heterocíclicos com 3 Anéis/farmacologia , Pigmentação/efeitos dos fármacos , Vinho/análise , Cromatografia Líquida de Alta Pressão , Compostos Heterocíclicos com 3 Anéis/síntese química , Compostos Heterocíclicos com 3 Anéis/química , Espectrometria de Massas , Estrutura Molecular , Oxirredução , Pigmentos Biológicos/análise , Pigmentos Biológicos/química
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