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The objective of this study was to assess the content of bioactive compounds, organic acids and antioxidantcapacity of grape juices from Isabel Precoce, BRS Carmem, BRS Cora and IAC 138-22 Máximo varieties grown onthe 'IAC 766?and 'IAC 572?rootstocks under tropical conditions in Brazil. In general, the color attributes of the'Isabel Precoce' juice were inferior to those of the other juices due to their low anthocyanin content. In contrast,'IAC 138-22 Máximo' juices showed the highest content of most individual anthocyanins,flavonols,trans-re-sveratrol and total phenolic compounds, and thus, higher antioxidant capacity. Except for 'BRS Carmem', all thejuices presented higher sugar accumulation when 'IAC 766?was used. This rootstock also contributed to theaccumulation oft-resveratrol and most of individual anthocyanins in the 'IAC 138-22 Máximo' juices. However,the monomeric anthocyanin content was higher in 'BRS Carmem' juices when 'IAC 572?rootstock was used. Made available in DSpace on 2020-01-09T18:11:08Z (GMT). No. of bitstreams: 1 1s2.0S0308814619305370main.pdf: 775844 bytes, checksum: 5a88a1296200366a72b3d96271ebce42 (MD5) Previous issue date: 2019

The objective of this work was to validate a method for direct determination in grape juice and wine of 1-kestose, nystose and raffinose oligosaccharides by reversed-phase high-performance liquid chromatography with refractive index detection using a new type of RP-C(18) column (150 × 4.6 mm, 4 µm) with polar end-capping. The validated methodology was also used to characterize grape juice and fine wine products from Northeastern Brazil; and presented suitable linearity, precision, recovery, limits of detection and quantification. The method presented good specificity, revealing that sugars, organic acids, and ethanol (the main interferences in refraction detection) did not influence the quantification of the studied oligosaccharides. The main oligosaccharide found was 1-kestose (approximately 50% of the samples), followed by raffinose (20% of the samples). The results obtained in this are an indication that grape juices and wines have the potential to be functional beverages in relation to the presence of prebiotics.

Residues from wine and juice processing still contain about 70% of the phenolic compounds in grapes. These compounds are valued for having several bioactive properties that are explored in the pharmaceutical and food sectors. This paper aims to summarize the most recent advances in the use of enzymatic techniques for the recovery of bioactive compounds from GP for industrial application. For this, we analyzed scientific articles and patent applications from the last 20 years in the main indexed and patent databases. Among the most used enzymes in the recovery of bioactive compounds in wastes, cellulases, pectinases, tannases, glucoamylases, and proteases such as trypsin and chymotrypsin, are the most important. As a result, extracts are obtained with greater retrieval of compounds such as anthocyanins, gallic acid, catechins, epicatechins, and trans-resveratrol and the improvement of coloring, anti-inflammatory, antioxidant and vasoprotective properties. Although the use of enzymes for the recovery of phenolics is an old strategy, the number of studies focusing on the functional characteristics and industrial applicability of the extracts obtained has been recently growing. PRACTICAL APPLICATIONS: Phenolic compounds have acted as anti-inflammatories, antioxidants, anticarcinogens, and antimicrobials, being additives or relevant ingredients for various products in the food and pharmaceutical industry. Although there are several techniques for extracting/recovering phenolics from grape pomace, there is still no agreement on which method is ideal. In recent years, several extractions methods have been applied in seeking optimized conditions to recover phenolics from grape residues. Among them, the use of enzymes has been gaining attention for being considered a green and promising technology. The present study aims to carry out a review that would bring a new perspective to the recovery of bioactive compounds from grape residues by enzymatic techniques, with a view to industrial purpose.

The technological and polyphenolic parameters of grapes for juice processing obtained from successive harvests were studied in semi-arid tropical viticulture. Red grapes ?BRS Violeta? and ?Isabel Precoce? were harvested during the same year and analyzed based on a multivariate approach that included climatic variations. The grapes were marked by variations in flavonoid compounds, particularly anthocyanins. Temperature, global radiation, air velocity and evapotranspiration rates were associated with higher accumulation of bioactive polyphenols in grape berries and juices. The temperatures in February were associated with higher antioxidant activity in grape peels, while the highest thermal amplitude in August and November favored the accumulation of anthocyanins up to 564 mg kg−1. Flavanols and procyanidin compounds were more abundant in seeds when the maximum thermal amplitude was 13.8 °C. The climatic data together with the polyphenolic results point out useful information about appropriate periods for harvesting grapes with high phenolic content in tropical areas. Made available in DSpace on 2022-09-09T17:05:35Z (GMT). No. of bitstreams: 1 Effects-of-successive-harvesting-in-the-same-year-2019.pdf: 385958 bytes, checksum: f7a2cfcb2a7faf9e9dab6a390668208a (MD5) Previous issue date: 2019

Organic acids and sugars are related to the chemical balance of wines and grape juices, besides exerting a strong influence on the taste balance and sensorial acceptance by consumers. The aim of this study was to validate a method for the simultaneous determination of sugars and organic acids in wines and grape juices by highperformance liquid chromatography (HPLC) with refractive index detection (RID) and diode array detection (DAD) and to characterize commercial products from northeast Brazil. The method provided values for linearity (R > 0.9982), precision (CV% < 1.4), recovery (76–106%) and limits of detection (0.003–0.044 g L?1 ) and quantification (0.008–0.199 g L?1 ) which are considered acceptable for application in the characterization of these types of matrices. Principal components analysis (PCA) was used to verify the applicability of the method in the quality control of the products and resulted in the correct separation of the samples according to their type of processing. The results obtained in the characterization of the samples studied showed high levels of glucose and fructose in grape juice and the organic acids content was similar to those found in products originating from other regions around the world. Keywords: Food analysis, Food composition, Vitis labrusca L, Beverage analysis, Wine, Grape juice, Sparkling wine, Sugars, Organic acids Made available in DSpace on 2018-03-23T01:03:02Z (GMT). No. of bitstreams: 1 CoelhoPereiraetalJFCA032018.pdf: 621033 bytes, checksum: 10876ce2b1aec4b4a5ef56567d3b0d10 (MD5) Previous issue date: 2018-03-22

A method for rapid determination of phenolic compounds by reversed-phase high-performance liquid chromatography (RP-HPLC), using a new column of faster resolution was validated and used to characterize commercial products produced with new grape Brazilian varieties of Northeast of Brazil. The in vitro antioxidant activity was also measured. The method showed linearity (R>0.9995), good precision (CV%

The aim of this study was to investigate the phenolic composition and antioxidant activity of commercial red wines produced from Vitis vinifera L. grapes grown in the Sao Francisco Valley (SFV), which is a tropical region in northeastern Brazil. All wines showed phenolic compound contents consistent with those of other traditional wine producing regions and high antioxidant activity. In total, 20 phenolic compounds were quantified by RP-HPLC-DAD-FD and the antioxidant activity was positively correlated with the content of syringic acid > peonidin 3-O-glucoside > ρ-coumaric acid > (+)-catechin, epigallocatechin gallate > cyanidin-3-O-glucoside > procyanidin A2 > (-)-epicatechin, highlighting the contribution of these bioactive compounds to the antioxidant potential of tropical wines. This study shows that it is possible to obtain wines with a good bioactive component and high antioxidant activity in tropical climates such as that of the SFV. The data reported herein contribute to our knowledge of the wine producing potential of new regions worldwide. Practical applications An important difference between the tropical viticulture practiced in the Sao Francisco Valley (SFV) and that of other traditional regions of the world is that in the SFV each vine can produce two harvests per year. Also, since this is a region with hot weather, high luminosity and abundant water for irrigation, wineries operate according to a particular scheme, according to the best period in which to harvest the grapes and to prune the vines. Also, the “step” system can be applied, where the harvesting is distributed within a certain period (e.g., one month, several months, or the whole year). Thus, it is possible to prepare wines throughout the year. This study contributes to gaining a better enological understanding of the wines produced in an atypical grape production region.

Les vins tropicaux sont ceux produits dans les régions vitivinicoles où plusieurs cycles végétatifs de la vigne peuvent se produire par an, avec au moins une récolte annuelle. Les principaux facteurs qui contribuent à cette vitiviniculture en basses latitudes sont : des températures élevées tout au long de l'année, des précipitations modérées ou insuffisantes, un rayonnement solaire abondant et de l'eau disponible pour l'irrigation. Des cycles continus peuvent se produire, et c'est alors le producteur qui décide quand tailler et quand récolter, selon les saisons des pluies, les demandes du marché, la structure physique et les types de vins produits. Les vins tropicaux sont produits dans le Vale do São Francisco, au nord-est du Brésil, depuis plus de trente ans. La vitiviniculture pratiquée dans la région est l'une des plus technicisées au monde, car elle exige un haut degré de connaissances de la part des viticulteurs et des techniciens, en termes de manipulation du terrain, ainsi que des connaissances différentes des ?nologues lors de la vinification. La région produit des vins effervescents de muscat, des vins effervescents traditionnels secs et demi-sec, des vins rouges encore jeunes et de garde, et des vins blancs jeunes, en plus des vins communs (de table), plus récemment. Cet article présente les caractéristiques de cette vitiviniculture jeune et différenciée, par rapport à celle pratiquée dans les pays producteurs traditionnels, ainsi que les résultats des recherches menées dans la région au cours des quinze dernières années, en partenariat avec les domaines viticoles. Made available in DSpace on 2020-12-19T09:03:18Z (GMT). No. of bitstreams: 1 Vins-tropicaux-de-la-region-semi-aride-du-Bresil.pdf: 2113140 bytes, checksum: 7964eafb4d725d59ab22ce3e79200bb0 (MD5) Previous issue date: 2020

Os vinhos tropicais são aqueles produzidos em regiões vitivinícolas onde pode ocorrer mais de um ciclo vegetativo da videira por ano, com pelo menos uma safra anual. OS principais fatores que colaboram para eta vitivinicultura de baixas latitudes são: temperaturas elevadas ao longo do ano, precipitação pluviométrica moderada ou deficitária, radiação solar em abundância e água disponível para a irrigação. Podem ocorrer ciclos contínuos, onde quem decide quando podar e quando colher é o produtor, em função das estações chuvosas, das demandas do mercado, da estrutura física e dos tipos de vinhos elaborados. No Vale do São Francisco, Nordeste do brasil, produz-se vinhos tropicais há mais de trinta anos. A vitivinicultura praticada na região é uma das mais tecnificadas do mundo, pois exige elevado grau de conhecimento dos viticultores e técnicos, em termos de manejo do campo, assim como diferentes conhecimentos dos enólogos durante as vinificações. São produzidos na região vinhos espumantes moscatéis, espumantes tradicionais secos e meio doces, vinhos tranquilos tintos jovens e de guarda e brancos jovens, além de vinhos comuns (de mesa), mais recentemente. Esse artigo apresenta as características desta vitivinicultura jovem e diferenciada, quando comparada àquela nos países produtores tradicionais, bem como resultados de pesquisas realizadas na região nos últimos quinze anos, em parceria comas vinícolas. Palavras-chave: uva, vinhos tropicais, Vale do São Francisco, qualidade, tipicidade, Pernambuco, Bahia Made available in DSpace on 2019-01-04T23:36:53Z (GMT). No. of bitstreams: 1 VinhosTropicaisdoSemiaridodoBrasil.pdf: 717552 bytes, checksum: de70294c676b8bc6bf764b1270d6e604 (MD5) Previous issue date: 2019-01-04