A survey on the composition of wines made with grapes produced by an organic system.

Summary There is concern about the health problems caused by pesticides in humans, which has led some grape producers to adopt organic procedures in their vineyards, and a certain amount of these grapes are directed to winemaking. Despite the approval awarded to this organic grape production by the certified organizations, there has been a demand to carry out a survey to determine the physicochemical composition of the wine derived from these products. Some of these wines were made from a single grape variety and others from more than one. For this survey, the samples consisted of five bottles of each type of wine, acquired from wineries and supermarkets in the Serra Gaúcha region, RS, Brazil. The analyses were carried out by physicochemical methods: volatile compounds by gas chromatography; minerals and trace elements by inductively coupled plasma optical emission spectrometry; and pesticide residues by liquid chromatography-mass spectrometry. The results showed that in general the physicochemical composition of these wines was within the limits established by Brazilian legislation. The mineral and trace element concentrations were very low and pesticide residues were not detected (MRL = 10 μg.kg?1) in any of the wines. Resumo: Há preocupação em relação a problemas causados por pesticidas no ser humano, o que levou uma parcela de viticultores a adotar procedimentos de agricultura orgânica em seus vinhedos. Assim, devido a essa preocupação, eles estão produzindo uva pelo sistema orgânico, sendo que uma parte dessa produção é direcionada à elaboração de vinho. Apesar de essas uvas terem sido aprovadas por entidades certificadoras, houve demanda para a realização de um levantamento para determinar a composição dos vinhos delas derivados. Portanto, cinco garrafas de cada tipo de vinho foram coletadas em vinícolas e supermercados da Serra Gaúcha, Rio Grande do Sul, sendo uma parte de vinhos varietais e outra, de cortes de diferentes variedades. As análises foram feitas por métodos físico-químicos: compostos voláteis, por cromatografia gasosa; minerais e elementos-traço, por espectrometria de emissão ótica com plasma acoplado indutivamente, e resíduos de pesticidas, por cromatografia líquida-espectrometria de massa. Os resultados mostram que a composição físico-química desses vinhos e dos minerais situou-se, em geral, dentro dos limites da legislação brasileira. As concentrações de minerais e de elementos-traço foram muito baixas, e não foram detectados resíduos de pesticidas (LMR = 10 μg.kg?1) em nenhum vinho.

Production of Syrah wines in tropical conditions of Northeast Brazil.

Twenty years ago, in the Northeast Brazil, a tropical semi-arid area, the production of tropical wines from some Vitis vinifera L. cultivars started. In this region, it is possible to harvest two times a year, between April and December, and nowadays Syrah is the most cultivated wine grape. Research works about irrigation rnanagement in Syrah started in 2000 at Brazilian Agricultural Research Corporation (Embrapa). The aim of this paper is to introduce some characteristics about the region where Syrah grapevines is being cultivated under irrigation in Northeast Brazil, and to present some results obtained from field experiments as well as some grape and wine charcteristics already determined.

Use of chemometrics to characterize tropical wines from different vintages and grape cultivars according to the 1H NMR spectroscopy data.

2011

Characterization of aromatic profiles in brazilian tropical wines determined by gas chromatography and multivariate statistical analysis.

2011

Aromatic stability of Syrah and Petit Verdot tropical wines from Brazil.

The production of fine wines in the Sub-middle of the São Francisco River Valley, Northeast of Brazil, is relatively recent, about twenty-five years ago. This region presents different characteristics, with a tropical semiarid climate, in a flat landscape. Presenting high annual average temperature, solar radiation and water in abundance for irrigation, it?s possible the scaling the grape harvests for winemaking throughout the year, allowing to obtain until two harvests per year. Several factors may affect the aromatic compounds in wines, such as viticulture practices, climatic conditions, cultivars and winemaking process. This study aimed to evaluate the aromatic stability of Syrah and Petit Verdot tropical wines elaborated in two different periods in the year. The grapes were harvested in the first and second semesters of 2009, in June and November. The wines were elaborated and then, they were bottled and analyzed in triplicate, thirty days and one year after bottling, by gas chromatography with ionization detector flame (GC-FID), to evaluate the profile and the stability of the aroma compounds. Principal component analysis was applied to discriminate between wine samples and to find the compounds responsible by the variability. The results showed that Syrah and Petit Verdot tropical wines presented different responses, for stability of higher alcohols, esters and carboxylic acids.

Influence of the vintage, clone and rootstock on the chemical characteristics of Syrah tropical wines from Brazil.

In the Northeast of Brazil, vines can produce twice a year, because annual average temperature is 26ºC, with high solar radiation and water availability for irrigation. Many cultivars have been tested according to their adaptation to the climate and soil, and the main variety used for red wines is Syrah. This work aimed to evaluate five clones of Syrah, grafted on two rootstocks, in two harvests of the second semester of 2009 and 2010, according to the chemical analyses of the wines.The clones evaluated were 100, 174, 300, 470 and 525, the rootstocks were Paulsen 1103 and IAC 313 (Golia x Vitis caribeae). Grapes were harvested in November 2009 and 2010 and the yield was evaluated. Climate characteristics of each harvest was determined and correlated to the results. Wines were elaborated in glass tanks of 20 L, with alcoholic fermentation at 25ºC for seven days, then wines were pressed and malolactic fermentation was carried out at 18ºC for 20 days. The following parameters were analyzed: alcohol content, dry extract, total anthocyanins, total phenolic index. High performance liquid chromatography was used to determine tartaric, malic, lactic and citric organic acids. Results showed that wines presented different concentrations of classical analyses, phenolics and organic acids according to the harvest date, rootstocks and clones. Principal component analysis was applied on data and clusters with wine samples were formed, explaining the variability, and results are discussed.

A concept for the viticulture of 'tropical wines'.

At worldwide level, the classical viticulture produces wines is almost all places in different climate types, where it is possible to obtain only one harvest per year. In these conditions, bud burst in vines occurs as a result of temperature raising at the end of the winter?beginning of spring. With the development of the vegetative cycle, grapes arrive to maturity/harvest period at the end of the summer?beginning of the fall season. After the fall of the leaves, vines undergo a dormant period with a vegetative repose (condition found also in some intertropical producer regions). A lot of grapes are produced for a long-time in the intertropical zone, but only a little part is used to winemaking. Considered a challenge in the past, to produce quality wines in the tropics became reality. The present industry of fine wines began about 30 years ago. Today, there are many commercial wineries in several countries in Occident and Orient in the tropical zone of the globe, like in Brazil, India, Thailand and Venezuela, producing some million liters of fine wines per year - called ?tropical wines?. This article analysis these climates, in relation to the particular viticulture adapted and developed, where it is possible to have more than one cycle per year, with one or more harvests per year. Based on the particularities of this viticulture, a characterization is proposed for the viticulture of ?tropical wines?. Some examples showing different tropical climates are presented.

Chemical and aromatic characteristics of Brazilian tropical wines.

Traditional winegrowing areas are located in temperate climate zones and allow to produce grapes only once per year. Tropical wines have been elaborated in India, Thailand, Venezuela and Brazil and present another kind of viticulture, as compared with countries located in temperate climate zones. Northeast of Brazil started wine production twenty six years ago. This region vines can produce two or three crops per year, depending of the cycle of different cultivars. Harvests can be scaled throughout the year, mainly between May and December, corresponding to the dry season. Red, white, rosé and sparkling wines are being elaborated in the region. The objective of this work was to determine the physico-chemical and aromatic characteristics of some tropical wines elaborated in Northeast of Brazil, with grapes harvested in November 2008. Wines were elaborated using traditional method with control of the alcoholic and malolactic fermentation temperatures, at 25 and 18ºC for red wines, respectively, and at 18ºC for alcoholic fermentation of the white wines. After stabilization and bottling and wines were analyzed to determine physico-chemical characteristics, like alcohol degree, pH, total and volatile acidities, dry extract, sulfur dioxide, total anthocyanin and total phenol index. Aromatic profile was determined by gas chromatography, while 19 esters and 6 superior alcohols were identified. Wines presented different chemical and aromatic characteristics according to different grape cultivars.

Characterization of the volatile profile of Brazilian Merlot wines through comprehensive two dimensional gas chromatography time-of-flight mass spectrometric detection.

Wine aroma is an important characteristic and may be related to certain specific parameters, such as raw material and production process. The complexity of Merlot wine aroma was considered suitable for comprehensive two-dimensional gas chromatography (GCGC), as this technique offers superior performance when compared to one-dimensional gas chromatography (1D-GC). The profile of volatile compounds of Merlot wine was, for the first time, qualitatively analyzed by HS-SPME-GCxGC with a time-of-flight mass spectrometric detector (TOFMS), resulting in 179 compounds tentatively identified by comparison of experimental GCxGC retention indices and mass spectra with literature 1D-GC data and 155 compounds tentatively identified only by mass spectra comparison. A set of GCGC experimental retention indices was also, for the first time, presented for a specific inverse set of columns. Esters were present in higher number (94), followed by alcohols (80), ketones (29), acids (29), aldehydes (23), terpenes (23), lactones (16), furans (14), sulfur compounds (9), phenols (7), pyrroles (5), C13-norisoprenoids (3), and pyrans (2). GCxGC/TOFMS parameters were improved and optimal conditions were: a polar (polyethylene glycol)/medium polar (50% phenyl 50% dimethyl arylene siloxane) column set, oven temperature offset of 10ºC, 7 s as modulation period and 1.4 s of hot pulse duration. Co-elutions came up to 138 compounds in 1D and some of them were resolved in 2D. Among the coeluted compounds, thirty-three volatiles co-eluted in both 1D and 2D and their tentative identification was possible only due to spectral deconvolution. Some compounds that might have important contribution to aroma notes were included in these superimposed peaks. Structurally organized distribution of compounds in the 2D space was observed for esters, aldehydes and ketones, alcohols, thiols, lactones, acids and also inside subgroups, as occurred with esters and alcohols. The Fischer Ratio was useful for establishing the analytes responsible for the main differences between Merlot and non-Merlot wines. Differentiation among Merlot wines and wines of other grape varieties were mainly perceived through the following components: ethyl dodecanoate, 1-hexanol, ethyl nonanoate, ethyl hexanoate, ethyl decanoate, dehydro-2-methyl-3(2H)thiophenone, 3-methyl butanoic acid, ethyl tetradecanoate, methyl octanoate, 1,4 butanediol, and 6-methyloctan-1-ol.

Sensory profiles of tropical wines produced in the São Francisco River Valley (Northeast Brazil).

2011

Aroma profile of Cabernet Sauvignon tropical wines produced in Northeastern of Brazil.

2011

The influence of climatic conditions on the phenolic composition of tropical Brazilian wines.

2012

Evaluation of the aroma stability of tropical white wines from Brazil.

2011

Determination of bioactive amines in tropical wines produced at Brazilian's Northeast.

The wine production in the region of the Sub-middle São Francisco river Valley has started there are few years ago.The region has a climate variability that allows to obtain two or three harvests per year, which influences significantly the composition of the grapes. This work aimed to evaluate the amount of amines present in white and red tropical wines produced in the Northeast of Brazil. The winemaking was done by the traditional method. After stabilizing the wines were bottled and then analyzed for the determination of the amines putrescine, spermidine and spermine, by thin layer chromatography (TLC). The harvests were in June (harvest I) and November (harvest II) 2009. The results showed that the edaphoclimatic conditions of the two harvests had significant influence (p> 0.05) on bioactive amines concentration, with high values for red wines. In addition, tropical wines from Sub-middle São Francisco river Valley showed adequate correlation between bioactive amines as compared to other wines in the world.

Effects de l'application d'acide gibbérellique (GA3) sur la qualité de raisins et de vins produits en climat tropical au Nord-Est du Brésil.

The honeydew moth Cryptoblabes gnidiella is the main problem for the wineries in the Northeast of the Brazil, because it attacks the bunch and reduces the quality of the grapes and the wines. In order to stretch out the bunch to facilitate the penetration of the insecticides, it was used gibberellic acid. Six treatments with different concentrations and different dates of application, and the control were compared. The bunches are compact, characteristic of the "Syrah" grapes in the region. The grape berries were analysed at harvest and wines were made by microvinifications. The grape berries showed different qualitative characteristics, as berry weight, number of berries. °Brix, total acidity and heterogeneity of the maturation. The microvinifications were carried out with 50 kg of grapeberries into glass bottles of 20 L at 22°C, for the alcoholic and malolactic fermentations, then stabilized and bottled. The wines were tasted by a panel of ten people and compared on smell and taste plans. The tasting results showed that the control treatment was the best graded wine. The application of gibberellic acid allowed to control the honeydew moth attack, but it caused a heterogeneity on grape maturation, with a lower quality of the grapes and wines compared to the control.