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1.
Food Chem ; 362: 130087, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34139571

RESUMO

EEM data recorded at different pH values was exploited by MCR-ALS in order to determine qualitative information about Brazilian red wines. In addition, the geographical traceability of wines produced in the Serra Gaúcha (Rio Grande do Sul) was carried out by DD-SIMCA considering 53 samples from the target class and 20 from other producing regions. The fluorescence signal corresponds to 9 EEMs recorded at different pH (3-11), generating four-way data. By MCR-ALS decomposition, eight factors were retrieved and related to typical chemical compounds found in red wine. In addition, the EEM pH data was used to build a one-class classification model, considering that MCR scores and all samples of the target class were properly recognised as belonging to the target class, with maximal sensitivity equal to 1. Samples of the non-target class were also adequately rejected by the model, and the specificity was found to be 0.97.


Assuntos
Vinho/análise , Vinho/classificação , Brasil , Fluorescência , Geografia , Concentração de Íons de Hidrogênio , Vinho/normas
2.
Sci. agric. ; 78(3): e20190233, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-28350

RESUMO

Double pruning extended the harvest season of wine grape (Vitis vinifera L.) to dry winter, enabling production of high quality wines in the southeastern Brazil. Winter harvest allows grapes to fulfill not only technological maturation, but also phenolic ripeness. Winter wines from Syrah grapes harvested from eight vineyards in southeastern Brazil during three harvests were analyzed for their chemical and aromatic composition after bottling and after ageing for 20, 30, and 42 months in bottle. Winter wines have high content of total phenolic compounds, which remained almost constant through ageing, as well as color intensity. Malvidin 3-O-glucoside stood out among anthocyanins, remaining 5-10 % after 39 months of ageing. Moreover, malvidin 3-O-glucoside-pyruvic acid was the main pyranoanthocyanin identified in winter wine. Polymerized pigments index ranged from 54 % at bottling to 80 % after 42 months of ageing. Young winter wines are rich in ester and monoterpene, as well as alcoholic volatile compounds responsible for ethereal, fruity, flowery, fresh and sweet aromas. Aged winter wines showed higher contents of furfural, geranyl ethyl ether, isoamyl decanoate, α-muurolene and α-calacorene, contributing to sweet, fruity and woody aromas. Syrah winter wines are characterized by high content of phenolic compounds and color stability, and keep good sensorial characteristics after ageing in bottle.(AU)


Assuntos
Vinho/análise , Vinho/classificação , Conservação de Alimentos/métodos , Compostos Fenólicos , Indústria de Engarrafamento
3.
Sci. agric ; 78(3): e20190233, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497947

RESUMO

Double pruning extended the harvest season of wine grape (Vitis vinifera L.) to dry winter, enabling production of high quality wines in the southeastern Brazil. Winter harvest allows grapes to fulfill not only technological maturation, but also phenolic ripeness. Winter wines from Syrah grapes harvested from eight vineyards in southeastern Brazil during three harvests were analyzed for their chemical and aromatic composition after bottling and after ageing for 20, 30, and 42 months in bottle. Winter wines have high content of total phenolic compounds, which remained almost constant through ageing, as well as color intensity. Malvidin 3-O-glucoside stood out among anthocyanins, remaining 5-10 % after 39 months of ageing. Moreover, malvidin 3-O-glucoside-pyruvic acid was the main pyranoanthocyanin identified in winter wine. Polymerized pigments index ranged from 54 % at bottling to 80 % after 42 months of ageing. Young winter wines are rich in ester and monoterpene, as well as alcoholic volatile compounds responsible for ethereal, fruity, flowery, fresh and sweet aromas. Aged winter wines showed higher contents of furfural, geranyl ethyl ether, isoamyl decanoate, α-muurolene and α-calacorene, contributing to sweet, fruity and woody aromas. Syrah winter wines are characterized by high content of phenolic compounds and color stability, and keep good sensorial characteristics after ageing in bottle.


Assuntos
Compostos Fenólicos , Conservação de Alimentos/métodos , Vinho/análise , Vinho/classificação , Indústria de Engarrafamento
4.
J Sci Food Agric ; 100(2): 465-482, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31452209

RESUMO

In contrast with the general trend of producing wine from the most famous grapevine varieties, associated with the French paradigm, such as Cabernet-Sauvignon, Merlot, Pinot Noir, Syrah, Sauvignon Blanc, and Chardonnay, there is a tendency to revalorize and preserve minority or autochthonous grapevine varieties worldwide. The South American wine region, where most of the varieties derived from varieties brought after European colonization, is not exempt from this. This has allowed new wines to be provided with distinctive identities that are markedly different from the current homogeneous wine production. Moreover, varietal homogenization increases vineyard genetic vulnerability in relation to the emergence of grapevine diseases, to which the commonly cultivated varieties are not resistant. This review summarizes the oenological potential of minority or autochthonous grapevine varieties cultivated within the South American wine region, focusing on Argentina, Chile, and Bolivia. © 2019 Society of Chemical Industry.


Assuntos
Vitis/química , Vinho/análise , América do Sul , Vitis/classificação , Vitis/genética , Vitis/crescimento & desenvolvimento , Vinho/classificação
5.
Food Chem ; 302: 125340, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419775

RESUMO

In this study, 83 wines representating four commercial categories: "Argentinean Malbec", "Brazilian Merlot", "Uruguayan Tannat" and "Chilean Carménère" were analyzed according to their phenolic and volatile compounds. The objective was to identify the chemical compounds that would typify each category. From approximately about 600 peaks obtained by chromatographic techniques, 169 were identified and 53 of them were selected for multivariate statistical analysis. Chilean Carménère was the best discriminated group by the methods applied in our study, followed by Argentinean Malbec. Brazilian Merlot mixed mainly with some Carménère, whileTannat mixed with all wines categories, especially Malbec. In general, Chilean Carménère wines can be characterized by a bluish color, higher amounts of sulphur dioxide, higher content of octanoic acid, isobutanol, ethyl isoamyl succinate and catechin and a smaller amount of quercetin. These data can contribute for further process of authenticity or typification of South American red wines.


Assuntos
Análise de Alimentos/estatística & dados numéricos , Fenóis/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise , Butanóis/análise , Caprilatos/análise , Catequina/análise , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/estatística & dados numéricos , Análise Multivariada , Quercetina/análise , América do Sul , Dióxido de Enxofre/análise , Vinho/classificação
6.
Braz. J. Pharm. Sci. (Online) ; 56: e18467, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1249175

RESUMO

The processing of grapes for the manufacture of juices and wines, generates large quantities of by-products rich in metabolites with antioxidant, antimicrobial, anti-inflammatory and cicatrizing activities. The high homology between human enzymes and snake venoms makes the latter valuable laboratory tools for the study of pathophysiological processes. Proteases and phospholipases A2 act in processes related to hemostasis and inflammatory response. Thus, in this work, dried pomace obtained from grape (Isabel, Niagara, Bordô, BRS Violeta and Blend cultivars) processing were evaluated on phospholipase, proteolytic, hemolytic and thrombolytic activities induced by snakes venoms and the content of phenolic compounds and minerals was evaluated. The dried pomace exerted inhibitory and potentiating actions in all analyzed activities. The enzymatic modulators present in the evaluated dried pomace have potential for therapeutic use, although their broad characterization is still necessary, in order to define adequate amounts and formulations to obtain efficacy and safety in their use.


Assuntos
Venenos de Serpentes/efeitos adversos , Vinho/classificação , Enzimas/análise , Compostos Fenólicos/análise , Fosfolipases A2/análise , Vitis/classificação , Resíduos Industriais/análise
7.
J Agric Food Chem ; 67(9): 2647-2659, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30758205

RESUMO

Sangiovese is the most widespread Italian red cultivar and constitutes the basis of internationally known wines such as Chianti and Brunello di Montalcino. Outside of Europe, Argentina is the largest producer, followed by the United States. This study sought to define and compare 2016 vintage Sangiovese wine composition from various production regions in California and Italy. Forty-six commercial Sangiovese wines from California and Italy were analyzed for volatile profile, color, phenolic, and elemental content. This study demonstrates that it is possible to determine regional differences among wines based on these chemical profiles. However, some Californian and Italian wine had similar chemical compositions. In order to compare Californian and Italian wines, Californian wine reference models were developed using the chemical parameters from Sangiovese wines, performing a Soft Independent Modeling of Class Analogy (SIMCA). To our knowledge, this is the first time that an extensive regionality study has been attempted for Sangiovese wines.


Assuntos
Frutas/química , Vitis/química , Vinho/análise , Argentina , California , Cromatografia Gasosa-Espectrometria de Massas , Itália , Metais/análise , Polifenóis/análise , Compostos Orgânicos Voláteis/análise , Vinho/classificação
8.
J Sci Food Agric ; 98(4): 1280-1290, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28741681

RESUMO

BACKGROUND: The geoviticultural multicriteria climatic classification (MCC) system provides an efficient guide for assessing the influence of climate on wine varieties. Paraná is one of the three states in southern Brazil that has great potential for the expansion of wine production, mainly due to the conditions that favour two harvests a year. The objective was to apply the geoviticultural MCC system in two production seasons. We used maximum, mean and minimum air temperature and precipitation for 1990-2015 for the state of Paraná. Air temperature and Precipitation were used to calculate the evapotranspiration and water balance. We applied the MCC system to identify potential areas for grapevine production for harvests in both summer and winter and then determined the climatic zones for each geoviticultural climate. RESULTS: Paraná has viticultural climates with conditions favourable for grapevine cultivation for the production of fine wines from summer and winter harvests. The conditions for the winter harvest provided wines with good coloration and high aromatic potential relative to the summer harvest. CONCLUSION: Chardonnay, Merlot, Pinot Blanc and Müller-Thurgau were suitable for regions with lower air temperatures and water deficits. Pinot Blanc and Müller-Thurgau were typical for the southern region of Paraná. © 2017 Society of Chemical Industry.


Assuntos
Clima , Frutas/crescimento & desenvolvimento , Estações do Ano , Vitis/crescimento & desenvolvimento , Vinho , Agricultura , Brasil , Especificidade da Espécie , Temperatura , Tempo (Meteorologia) , Vinho/classificação
9.
Food Chem ; 175: 174-80, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25577067

RESUMO

A study of Argentinean red wines was performed by direct injection of untreated wine samples into a liquid chromatography-mass spectrometry system, processing the collected data with two chemometric algorithms: multivariate curve resolution with alternating least-squares and discriminant unfolded partial least-squares (D-UPLS). The objectives were: (1) the chemometric resolution of profiles in the modes represented by elution time and m/z ratio, (2) the discrimination of samples according to varietal and/or geographical origin, and (3) the identification of key compounds helping to perform sample discrimination. The results indicate that all wine varietals can be adequately discriminated, and also three wine producing regions (located in the east, south and north of the Cuyo region) were differentiated from the remaining regions. The applied chemometric models allowed the tentative identification of anthocyanin compounds as responsible for both type of discriminations, in the case of D-UPLS by employing the concept of variables importance in the projection.


Assuntos
Antocianinas/análise , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Vinho/classificação , Argentina , Análise Discriminante , Análise dos Mínimos Quadrados , Vinho/análise
10.
J Food Sci ; 79(8): S1595-603, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25039987

RESUMO

Typicality is the set of sensory characteristics that identify a distinctive type of wine. Thus, the aim of this research was to identify the sensory characteristics that contribute to define typicality of young South American red wines based on their varietal and origin, and to evaluate the effect of the vintage on this identification. To achieve this objective, visual appearance, odor, and taste of 138 wines from 2 vintages were submitted to a sensory evaluation using a descriptive analysis complemented with the frequency of citation method, performed by wine experts. The intensity of 17 odor and taste attributes was evaluated using a 5 points rating structured scale. The panel performance evaluation demonstrated its high level of expertise and reproducibility. The wines were separated into 3 clusters by multivariate analyses. Cluster 1 was primarily composed of Carménère, Malbec, and Syrah wines from Chile. Cluster 2 was predominantly composed of Tannat wines from Uruguay and Brazil, while Cluster 3 contained a higher proportion of Malbec and Merlot wines from Argentina and Brazil. Cabernet Sauvignon was equally distributed into all clusters. Wine experts were able to identify the wines according to their varietal and origin, suggesting that there is typicality in young South American red wines. The combination of descriptive analysis with the frequency of citation was useful in characterizing most of the wines, but the typicality perceived by the panelists was not achieved by multivariate analysis. Vintage did not alter the sensory characterization of the wines, and this result could be due the new viticulture or oenological practices used by the winemakers to compensate the environmental variation.


Assuntos
Odorantes/análise , Paladar , Vinho/análise , Adulto , Argentina , Brasil , Chile , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reprodutibilidade dos Testes , Uruguai , Vitis/química , Vinho/classificação
11.
Food Chem ; 164: 427-37, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996354

RESUMO

The main changes in the volatile profile of base wines and their corresponding sparkling wines produced by traditional method were evaluated and investigated for the first time using headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry detection (GC×GC/TOFMS) and chemometric tools. Fisher ratios helped to find the 119 analytes that were responsible for the main differences between base and sparkling wines and principal component analysis explained 93.1% of the total variance related to the selected 78 compounds. It was also possible to observe five subclusters in base wines and four subclusters in sparkling wines samples through hierarchical cluster analysis, which seemed to have an organised distribution according to the regions where the wines came from. Twenty of the most important volatile compounds co-eluted with other components and separation of some of them was possible due to GC×GC/TOFMS performance.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Vinho/análise , Análise por Conglomerados , Análise de Componente Principal , Vinho/classificação , Vinho/normas
12.
Food Chem ; 141(4): 3897-905, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23993563

RESUMO

Headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry detection (GC×GC/TOFMS) was used to analyse the volatiles in five types of wines elaborated with grapes of Cabernet Sauvignon, Merlot, Chardonnay, Sauvignon Blanc and Pinot Noir varieties. Fisher ratio, principal component analysis (PCA) and stepwise linear discriminant analysis (SLDA) were used to develop a discriminant model and, as a result, 12 volatile compounds enabled differentiation and classification of wines according to grape cultivars. A detailed examination of GC×GC/TOFMS data showed that the use of one-dimensional gas chromatography with a mass spectrometric detector (1D-GC/MS) would probably result in misidentification of some of these 12 compounds, as they showed partial coelution with other components in the first chromatographic dimension.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas/métodos , Vitis/química , Vinho/análise , Análise Discriminante , Análise Multivariada , Vitis/classificação , Compostos Orgânicos Voláteis/química , Vinho/classificação
13.
Food Chem ; 141(2): 1055-62, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23790886

RESUMO

We studied the VOCs profile of three red wine varieties, produced in the Valley of Tulum (San Juan-Argentina), over 4 consecutive years. Our main goal was to verify if different wine varieties could be differentiated from their VOCs profile, considering changes induced by their age, the yeast inoculated and the type of alcoholic fermentation, establishing those compounds that could be used as chemical markers of a particular variety. Stepwise LDA of selected VOCs allowed 100% differentiation between studied wines, showing that high levels of 1-hexanol were characteristic for Malbec, while low level of ethyl caproate was characteristic for Bonarda. Using controlled fermentations, 1-hexanol, a pre-fermentative VOC, presented a similar trend in wines produced from different yeast; while other fermentative VOCs, like ethyl caproate and ethyl caprilate, presented lower levels for Bonarda but also for Syrah. To our knowledge, this is the first report on characterization of VOCs from Bonarda. Additionally, the quantitative analysis of VOCs profile, coupled to chemometrics, present a good alternative to differentiate wines from different varieties and also for studying wine fermentation.


Assuntos
Vitis/química , Compostos Orgânicos Voláteis/análise , Vinho/análise , Argentina , Biomarcadores/análise , Vinho/classificação
14.
Food Chem ; 140(1-2): 210-6, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23578635

RESUMO

Quantitative structure-property relationships (QSPRs) were applied to the aminograms obtained by HPLC in our laboratories for Torrontés and Merlot wines. Dragon theoretical descriptors were derived for a set of optimized amino acid structures with the purpose of establishing QSPR models. The statistical Replacement Method was used for designing the best multi-parametric linear regression models, which included structural features selected from a pool containing 1497 constitutional, topological, geometrical or electronic molecular descriptors. Predicted QSPR results were in good agreement with experimental amino acid profiles. The developed QSPR approach showed to be of practical value for distinguishing each wine varietal, and for calculating experimentally non-available amino acid concentrations of Torrontés and Merlot wines. It was also useful for assessing wine authenticity; the models were especially suitable for Merlot and Torrontés wines.


Assuntos
Aminoácidos/química , Vinho/análise , Biomarcadores/química , Relação Quantitativa Estrutura-Atividade , Vinho/classificação
15.
J Food Sci ; 78(3): C432-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23425149

RESUMO

UNLABELLED: Argentina is an important worldwide wine producer. In this country, there are several recognizable provinces that produce Sauvignon blanc wines: Neuquén, Río Negro, Mendoza, and San Juan. The analysis of the provenance of these white wines is complex and requires the use of expensive and time-consuming techniques. For this reason, this work discusses the determination of the provenance of Argentinean Sauvignon blanc wines by the use of UV spectroscopy and chemometric methods, such as principal component analysis (PCA), cluster analysis (CA), linear discriminant analysis (LDA), and partial least square discriminant analysis (PLS-DA). The proposed method requires low-cost equipment and short-time analysis in comparison with other techniques. The results are in very good agreement with results based on the geographical origin of Sauvignon blanc wines. PRACTICAL APPLICATION: This manuscript describes a method to determine the geographical origin of Sauvignon wines from Argentina. The main advantage of this method is the use of nonexpensive techniques, such as UV-Vis spectroscopy.


Assuntos
Espectrofotometria Ultravioleta/métodos , Vinho/análise , Vinho/classificação , Argentina , Análise por Conglomerados , Análise Discriminante , Concentração de Íons de Hidrogênio , Análise dos Mínimos Quadrados , Análise de Componente Principal
16.
J Sci Food Agric ; 93(1): 142-8, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22696032

RESUMO

BACKGROUND: Lactobacillus hilgardii, a wine lactic acid bacterium, is able to use arginine, through the arginine deiminase pathway with the formation of citrulline, a precursor of the carcinogen ethyl carbamate. The influence of different Argentine wine varieties (Merlot, Cabernet Sauvignon and Malbec), on bacterial growth and arginine metabolism was examined. Furthermore, the effect of different components normally present in wines on the enzyme activities of the arginine deiminase system was determined. RESULTS: Malbec wine under all conditions assayed (33, 50 and 100% supplemented wine:basal media) showed higher arginine consumption and citrulline production than the other wines, as well as the highest bacterial growth and survival of Lactobacillus hilgardii X1B. Glucose and L-malic inhibited both arginine deiminase enzymes while fructose and citric acid only inhibited arginine deiminase. The red wines assayed in this study had different composition, and this is an explanation for the different behavior of the bacterium. CONCLUSION: The highest citrulline production in Malbec wine could be correlated with its lower concentrations of glucose, fructose, citric and phenolic acid than the other wines. Therefore, a wine with lower concentration of these sugars and acids could be dangerous due to the formation of ethyl carbamate precursors.


Assuntos
Arginina/metabolismo , Ácidos Carboxílicos/farmacologia , Carcinógenos/metabolismo , Citrulina/biossíntese , Hexoses/farmacologia , Lactobacillus/efeitos dos fármacos , Vinho/microbiologia , Argentina , Ácidos Carboxílicos/análise , Ácido Cítrico/farmacologia , Frutose/farmacologia , Frutas/química , Glucose/farmacologia , Hexoses/análise , Humanos , Concentração de Íons de Hidrogênio , Hidrolases/metabolismo , Hidroxibenzoatos/farmacologia , Lactobacillus/metabolismo , Malatos/farmacologia , Especificidade da Espécie , Uretana/metabolismo , Vitis/química , Vitis/classificação , Vinho/análise , Vinho/classificação
17.
São Paulo; s.n; 2011. 140 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-640014

RESUMO

O vinho tinto é rico em compostos fenólicos com atividade antioxidante, capazes de inativar espécies reativas de oxigênio, minimizando danos celulares oriundos do estresse oxidativo, proporcionando uma redução de risco para doenças crônicas não transmissíveis. Assim, os objetivos desta pesquisa foram identificar associações entre a atividade antioxidante in vitro e fatores relacionados ao tipo de uva, região de produção, perfil sensorial, safra, valor comercial e concentração de compostos fenólicos de vinhos tintos produzidos no Brasil, Chile e Argentina. Inicialmente, os vinhos brasileiros (n=29) foram avaliados em relação à atividade antioxidante (ORAC e DPPH), cor instrumental e compostos fenólicos majoritários, no intuito de verificar qual classe de fenólicos estaria associada com a atividade antioxidante. Verificou-se que tanto os compostos fenólicos totais como os flavonóides totais, com destaque aos flavonóides não-antociânicos, se associaram significativamente (p<0,05) com a atividade antioxidante. Em um segundo passo, as características sensoriais, a cor, o valor comercial e a atividade antioxidante das 80 amostras de vinhos Sul-Americanos, distribuídas em Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), e vinhos de uvas americanas (Vitis labrusca) (n=7) foram avaliados usando estatística multivariada, objetivando-se verificar se a qualidade sensorial das amostras estaria associada com o valor comercial, cor, e à atividade antioxidante. De uma forma geral, os vinhos chilenos e argentinos apresentaram maior atividade antioxidante, valor comercial, intensidade de odor, qualidade sensorial, índice de acidez e taninos, ao passo que os vinhos brasileiros obtiveram os menores valores para os atributos sensoriais. Os vinhos de uvas americanas apresentaram menores valores para todas as variáveis. As varietais Syrah, Malbec e Cabernet Sauvignon apresentaram maior capacidade antioxidante e melhores características ...


Red wine is rich in phenolic compounds with antioxidant activity, being able to buffer reactive oxygen species, thus decreasing the risk of non-transmissible chronic diseases. In this regard, the objectives of this research aimed at identifying associations between the in vitro antioxidant activity and factors related to grape varietal, region of production, sensory profile, vintage, color, commercial value, and concentration of phenolic compounds of red wines produced in Brazil, Chile, and Argentina. Initially, the Brazilian red wines (n = 29) were assessed in relation to antioxidant activity, instrumental color, and major phenolic compounds with the objective to verify which phenolic class was associated with the antioxidant activity. Both the total phenolic compounds and total flavonoids, with special attention to non-anthocyanin flavonoids, were significantly associated with the antioxidant activity. In a second step, the sensory characteristics, color, commercial value, and antioxidant activity of the 80 red wine samples, which were distributed in Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), and table wines (Vitis labrusca) (n=7) were evaluated using multivariate statistical techniques, with the aim to verify how the overall perception of quality of wines was related to commercial value, color and antioxidant activity. In a general way, te Chilean and Argentinean red wines displayed a higher antioxidant activity, commercial value, intensity of odors, sensory perception of quality, acidity level, and tannin level, whereas the Brazilian samples obtained the lowest values for the sensory attributes. The table wines presented the lowest values for all response variables. Syrah, Malbec and Cabernet Sauvignon varietals presented the highest antioxidant activity and most favorable sensory features, and this result was independent of wine's vintage and origin. As a last step, the wines produced with V. vinifera grapes …


Assuntos
Antioxidantes/análise , Antioxidantes/classificação , Técnicas In Vitro , América do Sul , Relação Estrutura-Atividade , Paladar , Vinho/análise , Vinho/classificação , Compostos Fenólicos/análise , Compostos Fenólicos/estatística & dados numéricos , Análise Multivariada , Radicais Livres/análise , Limiar Gustativo
18.
Appl Spectrosc ; 61(11): 1163-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18028694

RESUMO

Wine tannins are fundamental to the determination of wine quality. However, the chemical and sensorial analysis of these compounds is not straightforward and a simple and rapid technique is necessary. We analyzed the mid-infrared spectra of white, red, and model wines spiked with known amounts of skin or seed tannins, collected using Fourier transform mid-infrared (FT-MIR) transmission spectroscopy (400-4000 cm(-1)). The spectral data were classified according to their tannin source, skin or seed, and tannin concentration by means of discriminant analysis (DA) and soft independent modeling of class analogy (SIMCA) to obtain a probabilistic classification. Wines were also classified sensorially by a trained panel and compared with FT-MIR. SIMCA models gave the most accurate classification (over 97%) and prediction (over 60%) among the wine samples. The prediction was increased (over 73%) using the leave-one-out cross-validation technique. Sensory classification of the wines was less accurate than that obtained with FT-MIR and SIMCA. Overall, these results show the potential of FT-MIR spectroscopy, in combination with adequate statistical tools, to discriminate wines with different tannin levels.


Assuntos
Biologia Computacional , Limiar Sensorial , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Taninos/análise , Vinho/análise , Vinho/classificação , Análise Discriminante , Odorantes , Taninos/classificação , Paladar , Vitis/química
19.
J Agric Food Chem ; 55(9): 3675-80, 2007 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-17407309

RESUMO

A formal compositional study of the proanthocyanidins of Vitis vinifera L. cv. Carménère was conducted in this work. We first characterized the polymeric proanthocyanidins of Carménère skins, seeds, and wines. In addition, the wine astringency was analyzed and compared with Cabernet Sauvignon. Although Carménère wines had a higher proanthocyanidin concentration and mean degree of polymerization than Cabernet Sauvignon wines, the former wines were perceived as less astringent. The low seed/skin proportion in Carménère wines as compared to other varieties, as evidenced by the reduced number of seeds per berry and the higher amount of epigallocatechin subunits of Carménère wine proanthocyanidins, could explain this apparent paradox.


Assuntos
Frutas/química , Proantocianidinas/análise , Vitis/química , Vinho/análise , Chile , Paladar , Vinho/classificação
20.
Biocell ; Biocell;30(1): 1-7, abr. 2006. tab
Artigo em Inglês | LILACS | ID: lil-448071

RESUMO

Argentinean Vitis vinifera cultivars although originated from Europe, have clear ampeIographic and genotypic differences as compared with the European cultivars currently used in wine making. In vitro evaluation of salt tolerance has been used in many species. Our hypothesis was that Argentinean cultivars are more tolerant to salinity than European ones. Three European cultivars, Malbec, Cabernet Sauvignon and Chardonnay and four Argentinean cultivars, Cereza, Criolla Chica, Pedro Gimenez and Torrontes Riojano were tested by in vitro culture. Treatments included: 1) Control, 2) 60 mEq/L of a mixture of three parts of NaCl and one part of CaCl2 and 3) 90 mEq/L of the salt mixture. Results from two experiments (I and II) are reported. No differences were found in plant survival, expressed as % of the respective control, among cultivars. Leaf area, leaf, stem and total dry matter (DM) in Experiment I and leaf area, leaf number and leaf, stem, root and total DM in Experiment II, were higher in Argentinean cultivars than in European ones. We conclude that Argentinean cultivars show better performance in growing under salinity, especially in the highest salt concentration. Differences among cultivars, inside each group, were found for most of the measured variables.


Assuntos
Produção Agrícola , Cloreto de Sódio/efeitos adversos , Meios de Cultura/análise , Solos Salitrosos , Vitis/crescimento & desenvolvimento , Vitis/fisiologia , Argentina , Europa (Continente) , Fenômenos Fisiológicos Vegetais , Vinho/classificação
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