35 research outputs found
Anthocyanin composition of young red wine cv. Ruby Cabernet and Syrah: effect of time and storage conditions.
The aim of this study was to evaluate the evolution of anthocyanins in red wines for 12 months of storage in bottles in two different conditions. The wine samples cv. Ruby Cabernet and cv. Syrah (Vitis vinifera L.) used for this study were produced in the Sub-middle São Francisco Valley, in the Northeast Region of Brazil, during the 2013 harvest
Anthocyanin composition of young red wine cv. Ruby Cabernet and Syrah: effect of time and storage conditions.
The aim of this study was to evaluate the evolution of anthocyanins in red wines for 12 months of storage in bottles in two different conditions. The wine samples cv. Ruby Cabernet and cv. Syrah (Vitis vinifera L.) used for this study were produced in the Sub-middle São Francisco Valley, in the Northeast Region of Brazil, during the 2013 harvest
COPIGMENTAÇÃO INTRA E INTERMOLECULAR DE ANTOCIANINAS: UMA REVISÃO
Este trabalho apresenta revisão de literatura sobre a
reação de copigmentação intra e intermolecular e sua
relevância na estabilização de antocianinas. Flavonóides
não-antociânicos, alcalóides, aminoácidos e
nucleosídios, entre outros, podem atuar como
copigmentos de antocianinas. O aumento na estabilidade
das antocianinas ocorre devido à proteção fornecida
pelo copigmento frente à reação de hidratação do cátion
flavilium. Estudos ainda são necessários para avaliar a
estabilidade de antocianinas adicionadas de copigmentos
em sistemas modelos de alimentos, visando aumentar o
espectro de aplicação dessas como corantes em
alimentos e bebidas.
ANTHOCYANINS INTRA AND INTERMOLECULAR COPIGMENTATION: A
REVIEW
Abstract
This research presents literature review about the reaction of intra and intermolecular
copigmentation and its revealance in anthocyanins stabilization. Non-anthocyanic
flavonoids, alkaloids, amino acids, nucleosides, and others, can act as anthocyanins
copigments. The increase in the stability of anthocyanins occurs due to protection
supplied by the copigment towards the hydratation reaction of colored flavylium
cation. Studies to evaluate anthocyanins stabilization added of copigments in food
models system are still necessary, aiming to enhance the application spectra as
colorants in foods and beverages
Propiedades emulsificantes y espumantes de las proteínas de harina de cacahuate (Arachis hypogaea Lineau)
The functional properties of proteins present in peanut (Arachis hypogaea Lineau) flour were studied. The influence of the pH and protein solubility on emulsifying and foaming properties of peanut flour was evaluated. The isoelectric point (Ip) of these proteins was found at the pH of 4,0; and the isoelectric region between pH 3,0 and 5,0. The evaluated surface properties decreased in the isolectric region. The emulsifying activity and time stability (30 and 120 minutes) significantly decreased at the pI; the emulsifying stability at the temperature of 80°C decreased in all the isoelectric region until the pH of 6,0. The foaming activity had the best values at the pH of 2,0. The correlation between protein solubility and surface properties were more significant for emulsifying properties than for foaming properties.Se estudiaron las propiedades funcionales de las proteínas presentes en la harina de cacahuate (Arachis hypogaea Lineau). Fue evaluada la influencia que tienen el pH y la solubilidad proteica sobre las propiedades emulsificantes y espumantes de las proteínas de harina de cacahuate. El punto isoeléctrico (pI) de estas proteínas se encuentra a pH 4,0; mientras que la región isoeléctrica está entre los valores de pH de 3,0 y 5,0. Las propiedades de superficie evaluadas disminuyeron en la región isoeléctrica, siendo que la actividad emulsificante y la estabilidad emulsificante en los tiempos de 30 y 120 minutos disminuyeron fuertemente en el pI; las estabilidades emulsificantes en relación a la temperatura (80 ºC) diminuyeron en toda la región isoeléctrica extendiéndose hasta el pH 6,0. La actividad espumante mostró sus mejores valores a pH 2,0. Las correlaciones entre la solubilidad protéica y las propiedades de superficie fueron más importantes para las propiedades emulsificantes que para las espumantes
Rapid determination of flavonoids and phenolic acids in grape juices and wines by RP-HPLC/DAD: Method validation and characterization of commercial products of the new Brazilian varieties of grape.
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% < 2.78), recovery (91.8?105.1%) and limits of detection (0.04?0.85 mg L-1 ) and quantification (0.04?1.41 mg L-1 ) according to other methods previously published with the difference of a run time of only 25 min. The results obtained in the characterization of the samples differed for juices and wines from other world regions, mainly because of the high values of (-)-epigallocatechin and trans-caftaric acid. The products analyzed showed high antioxidant activity, especially the wine samples with values higher than those from wines of different regions of the worl
Phenolic compounds, organic acids and antioxidant activity of grape juices produced from new Brazilian varieties planted in the Northeast Region of Brazil.
The phenolic compounds, organic acids and the antioxidant activity were determined for grape juice samples from new Brazilian varieties grown in the Sub-middle São Francisco Valley in the Northeast Region of Brazil. The results showed that the Brazilian grape juices have high antioxidant activity, which was significantly correlated with the phenolic compounds catechin, epicatechin gallate, procyanidin B1, rutin, gallic acid, caffeic acid, p-coumaric acid, pelargonidin-3-glucoside, cyanidin-3-glucoside, cyaniding-3,5-diglucoside and delphinidin-3-glucoside. The produced juice samples showed higher concentrations of trans-resveratrol than those observed in juices made from different varieties of grapes from traditional growing regions. Organic acids concentrations were similar to those of juices produced from other classical varieties. It was demonstrated that it is possible to prepare juices from grapes of new varieties grown in the Northeast of Brazil containing a high content of bioactive compounds and typical characteristics of the tropical viticulture practised in the Sub-middle São Francisco Valley
The complete genome sequence of Chromobacterium violaceum reveals remarkable and exploitable bacterial adaptability
Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) ≈500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) wide-spread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications
Phenology and ripening of Vitis vinifera L. grape varieties in São Joaquim, southern Brazil: a new South American wine growing region
This study investigated the phenology and the ripening characteristics of Vitis vinifera grapes Cabernet Franc, Merlot, Sangiovese and Syrah in two consecutive vintages (2006 and 2007) in order to evaluate the adaptation of these recently cultivated varieties in São Joaquim, Santa Catarina State, Brazil. The phenological data observed, budburst, blooming, setting, véraison and harvest were monitorated. In order to monitor the ripening levels of pH, total acidity, total soluble solids, maturation Índex, total monomeric anthocyanins, total polyphenols index and color index were analyzed.The results show that the phenological cycle from budburst to harvest occurred within a frame time of 191 and 219 days and the heat summation requirements varied between 1,161 and 1,340 GDD. The summing of the GDD results during the phenological cycle of the grapevines (budburst - harvest) characterizes São Joaquim-SC as "Region I" (< 1,389 GDD), that is, a "cold region" in terms of the Winkler Regions.The climatic parameters influenced the grapevine phenology and the grape ripening. The results showed that these different grape varieties had typical characteristics at maturity and indicated that they have potential for the production of fine wines, suggesting that São Joaquim-SC is suitable for Vitis vinifera grape growing.Se estudio la fenología y las características de maduración de uvas Vitis vinifera Cabernet Franc, Merlot, Sangiovese y Syrah en dos vendimias consecutivas (2006 y 2007), con el fin de evaluar la adaptación de estas variedades cultivadas recientemente en San Joaquim, Santa Catarina (Brasil). Las características fenológicas observadas fueron: brotación, floración, cuajado, envero y vendimia. Se analizaron los niveles de maduración de pH, acidez total, sólidos solubles totales, índice de maduración, el total de antocianos, índice de los polifenoles totales y el índice de color. Los resultados muestran que el ciclo fenológico desde la brotación hasta la vendimia se produjo entre 191 y 219 días y con requerimientos de acumulación de calor de 1.161 y 1.340 grados día. El resumen de los resultados de suma térmica durante el ciclo fenológico de la vid (brotación -cosecha) caracteriza a São Joaquim-SC como "Region I" (<1.389 grados día), es decir, una "zona fría", en términos de las Regiones Winkler. Los parámetros climáticos influyeron en la fenología de la vid y la maduración de la uva. Los resultados mostraron que estas variedades de uva tenían características típicas en la madurez y que ellos tienen un potencial para la producción de vinos finos, lo que sugiere que San Joaquim-SC es adecuado para el crecimiento de uvas Vitis vinifera