Performance of hydroxycinnamic esters during white wine vinification

O objetivo deste trabalho foi determinar o conteúdo de ácido caftárico e cutárico em mostos e vinhos brancos, nos vários estágios da vinificação. Foram utilizadas cultivares de uva branca, Chenin Blanc e Sauvignon Blanc (Vitis vinifera) cultivadas em Santana do Livramento, RS, e Niágara (Vitis labrusca), cultivada em Santa Maria, RS, das safras de 1997, 1998 e 1999. O conteúdo desses compostos foi determinado por meio de cromatografia líquida de alta eficiência, na fase de esmagamento da uva, durante a fermentação, e no vinho pronto para o consumo. Concentrações de ácido caftárico foram geralmente mais altas do que as de ácido cutárico, tanto em mosto quanto em vinho. A quantidade média de ácido caftárico no mosto, nas três cultivares, foi de 61,25 mg/L, enquanto no vinho correspondente, foi de 32,10 mg/L, comprovando a diminuição deste composto durante a fermentação. Comportamento semelhante foi observado em relação ao ácido cutárico (22,63 e 9,00 mg/L, respectivamente no mosto e no vinho). Em amostras coletadas seis meses após o engarrafamento, observou-se também uma diminuição dos dois compostos, porém em menor proporção.The objetive of this work was to quantify caftaric acid and cutaric acid in musts and wines during the vinification phases. White grape cultivars Chenin Blanc and Sauvignon Blanc (Vitis vinifera) cultivated in Santana do Livramento, RS, and Niágara (Vitis labrusca) cultivated in Santa Maria, RS, Brazil, were used in 1997, 1998 and 1999. Content of the compounds was determined through high performance liquid chromotography in grape crushing, during fermentation and when the wine was ready to be consumed. Generally, the caftaric acid concentrations were higher than the cutaric acid concentrations, in musts as much as in wine. The average quantity of caftaric acid in must, in the three cultivars, was 61.25 mg/L, while in the corresponding wine it was 32.10 mg/L, proving a decrease of this compound during fermentation. A similar performance was observed for cutaric acid (22.63 and 9.00 mg/L, respectively for must and wine). In samples collected six months after bottling, a decrease was also observed in these two compounds, but in a smaller proportion

Ultrasound in the postharvest treatment of grapes: impact on the extractability and phenolic composition of juice and wine

Ultrasound has gained attention from the food industry because its properties, including chemical and physical reactions, enable a wide range of commercial applications. One of the most popular applications is the optimization of extraction of bioactive substances. Among the most recent applications is its use in postharvest of fruits and vegetables, wherein ultrasound functions as a possible elicitor agent promoting the synthesis of phenolic compounds. These substances are important in defining the chemical and sensory characteristics of juices, wines and other grape products because the concentration and extraction capacity of these compounds in grapes directly influence the product quality. Thus, this study aimed to evaluate the application of ultrasound in American and vinifera grapes of different harvests with regard to its effects on fruit extractability and concentration of phenolic compounds in elaborated juice and wine. The results indicated that, under certain conditions, ultrasound could lead to a significant increase in the anthocyanin concentration in ‘Isabella’ grapes and its juice. On the other hand, in ‘Cabernet Sauvignon’ grapes, most of the treatments did not indicate positive results in the tested parameters and tended to promote degradation of anthocyanins at significant levels. However, the observed effects varied depending on the harvest conditions and cultivar characteristics

Acute consumption of bordo grape juice and wine improves serum antioxidant status in healthy individuals and inhibits reactive oxygen species production in human neuron-like cells

Few studies investigated the biological effects of American grape cultivars. We investigated the metabolic response after acute consumption of grape juice or wine from Bordo grapes (Vitis labrusca) in a placebo-controlled crossover study with fifteen healthy volunteers. Blood samples were collected 1 hour after the intake of 100 mL of water, juice, or wine to measure TBARS, ABTS, FRAP, glucose, and uric acid levels. To evaluate differences in cellular response, intracellular reactive species production (DCFH-DA) and metabolic mitochondrial viability (MTT) were assessed after exposure of human neuron-like cells (SH-SY5Y) to juice or wine. Glycemia was reduced after juice or wine consumption, whereas blood levels of uric acid were reduced after juice consumption but increased after wine consumption. Juice and wine consumption reduced plasma lipid peroxidation and increased plasma antioxidant capacity (ABTS and FRAP assays). Furthermore, juice inhibited H2O2-induced intracellular production of reactive species (RS) and increased the viability of SH-SY5Y cells. In contrast, wine (dealcoholized) exhibited a per se effect by inducing the production of RS and reducing cell viability. )ese results indicate a positive impact of acute consumption of Bordo juice and wine on human oxidative status, whereas only juice had protective effects against oxidative stress-induced cytotoxicity

Influência da maceração carbônica e da irradiação ultravioleta nos níveis de trans-resveratrol em vinhos de uva cabernet sauvignon

The moderate consumption of wine reduces the risks of heart diseases significantly. This effect is attributed to the polyphenols found in the wine, in special to resveratrol (3,5,4'-trihidroxistilbene) that it is a phytoalexin found in the various parts of the vine, including in the skin of the grape, as well as in other species of plants. Grapes of cultivar Cabernet Sauvignon had been submitted to the irradiation with ultra-violet light and carbonic maceration and after fermented. It was proceeded all collection from samples during the experiment, which later had been analyzed how much to the concentration of trans-resveratrol using the Liquid Chromatography of High Efficiency. The of the content of trans-resveratrol was ascendent during the vinification phases. Differences had occurred in the end of the fermentation where the samples of wines with carbonic maceration had presentes low decline, possibly for the CO2 atmosphere in which they were stored, in this way, inhibiting the formation of resveratrol. At the end of the main fermentation, the concentration of trans-resveratrol was 15 mg.L-1 in all treatments, arriving of 1.5 mg.L-1, in average, at the end of storage period.O consumo moderado de vinho reduz significativamente os riscos de doenças cardiovasculares. Este efeito é atribuído aos polifenóis presentes no vinho, em especial ao resveratrol (3,5,4'-triidroxiestilbeno), que é uma fitoalexina encontrada em várias partes da videira, principalmente na casca da uva, assim como em outras espécies de plantas. Uvas da cultivar Cabernet Sauvignon foram submetidas à irradiação com luz ultravioleta e maceração carbônica e após fermentadas. Procedeu-se à coleta de amostras durante todo o experimento, as quais foram posteriormente analisadas quanto ao teor de trans-resveratrol através da Cromatografia Líquida de Alta Eficiência. Os resultados do trabalho demonstram que a evolução do conteúdo de trans-resveratrol foi ascendente durante as fases da fermentação. Diferenças ocorreram no final da fermentação, em que as amostras de vinhos com maceração carbônica apresentaram leve declínio, possivelmente pela atmosfera de CO2 na qual ficaram armazenadas, inibindo a formação do resveratrol. Ao final da fermentação principal a concentração de trans-resveratrol foi de 15 mg.L-1 em todos os tratamentos, chegando a 1,5 mg.L-1, em média, no final do período de estocagem

Acute Consumption of Bordo Grape Juice and Wine Improves Serum Antioxidant Status in Healthy Individuals and Inhibits Reactive Oxygen Species Production in Human Neuron-Like Cells

Few studies investigated the biological effects of American grape cultivars. We investigated the metabolic response after acute consumption of grape juice or wine from Bordo grapes (Vitis labrusca) in a placebo-controlled crossover study with fifteen healthy volunteers. Blood samples were collected 1 hour after the intake of 100 mL of water, juice, or wine to measure TBARS, ABTS, FRAP, glucose, and uric acid levels. To evaluate differences in cellular response, intracellular reactive species production (DCFH-DA) and metabolic mitochondrial viability (MTT) were assessed after exposure of human neuron-like cells (SH-SY5Y) to juice or wine. Glycemia was reduced after juice or wine consumption, whereas blood levels of uric acid were reduced after juice consumption but increased after wine consumption. Juice and wine consumption reduced plasma lipid peroxidation and increased plasma antioxidant capacity (ABTS and FRAP assays). Furthermore, juice inhibited H2O2-induced intracellular production of reactive species (RS) and increased the viability of SH-SY5Y cells. In contrast, wine (dealcoholized) exhibited a per se effect by inducing the production of RS and reducing cell viability. These results indicate a positive impact of acute consumption of Bordo juice and wine on human oxidative status, whereas only juice had protective effects against oxidative stress-induced cytotoxicity