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Oxovitisin A
Oxovitisin A is an oxovitisin, a type of pyranoanthocyanin with a pyranone ( 2-pyrone) component. It is found in aged Port wines. It does not contain an oxonium ion component (flavylium cation), as anthocyanins do. Therefore, it does not have an absorption maximum at 520 nm. Oxovitisins are stable yellowish Varieties of the color yellow may differ in hue, chroma (also called saturation, intensity, or colorfulness) or lightness (or value, tone, or brightness), or in two or three of these qualities. Variations in value are also called tints and sha ... pigments with similar unique spectral features, displaying only a pronounced broad band around 370 nm in the UV−vis spectrum. It is an oxidative derivative of carboxypyranomalvidin-3-glucoside (vitisin A).Oxovitisins: A New Class of Neutral Pyranone-anthocyanin Derivatives in Red Wines. Jingren He, Joana Oliveira, Artur M. S. Silva, Nuno Mateus and Victor De Freitas, J. Agric. Food Chem., 2010, 58 (15), pages 8814–8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxovitisin
Oxovitisins are a type of pyranoanthocyanin with a pyranone ( 2-pyrone) component found in aged Port wines. They do not contain an oxonium ion component (flavylium cation), as anthocyanins do. Therefore, they do not have an absorption maximum at 520 nm. Oxovitisins are stable yellowish Varieties of the color yellow may differ in hue, chroma (also called saturation, intensity, or colorfulness) or lightness (or value, tone, or brightness), or in two or three of these qualities. Variations in value are also called tints and sha ... pigments with similar unique spectral features, displaying only a pronounced broad band around 370 nm in the UV−vis spectrum. Examples * Pyranone-malvidin-3-glucoside ( Oxovitisin A) * Pyranone-malvidin-3-coumaroylglucosideOxidative formation and structural characterisation of new α-pyranone (lactone) compounds of non-oxonium nature originated from fruit anthocyanins. Jingren He, Artur M.S. Silva, Nuno Mateus and Victor de Freitas, Food ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyranoanthocyanin
The pyranoanthocyanins are a type of pyranoflavonoids. They are chemical compounds formed in red wines by yeast during fermentation processes or during controlled oxygenation processes during the aging of wine. The different classes of pyranoanthocyanins are carboxypyranoanthocyanins, methylpyranoanthocyanins, pyranoanthocyanin-flavanols, pyranoanthocyanin-phenols, portisins, oxovitisins and pyranoanthocyanin dimers; their general structure includes an additional ring (formed between the OH group at C-5 and the C-4 of the anthocyanin pyranic ring) that may have different substituents linked directly at C-10. Examples * Carboxypyranoanthocyanidins, can be considered markers of microoxygenation techniques * Hydroxyphenyl-pyranoanthocyanins * Vitisin A and B * Pinotins * Portosins (vinylpyranoanthocyanins) Vitisin A type * Cyanidin-3-O-glucoside-pyruvic acid (m/z of +H ion:517, λmax 506 nm) * Cyanidin-3-O-acetylglucoside-pyruvic acid (559 - 507) * Cyanidin-coumar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Port Wine
Port wine (also known as vinho do Porto, , or simply port) is a Portuguese fortified wine produced in the Douro Valley of northern Portugal. It is typically a sweet red wine, often served with dessert, although it also comes in dry, semi-dry, and white varieties. Other port-style fortified wines are produced outside Portugalin Argentina, Australia, Canada, France, India, South Africa, Spain, and the United Statesbut under the European Union Protected Designation of Origin guidelines, only wines from Portugal are allowed to be labelled "port". Region and production Port is produced from grapes grown and processed in the demarcated Douro region.Porter, Darwin & Danforth Price (2000) ''Frommer's Portugal'' 16th ed., p. 402. IDG Books Worldwide, Inc. The wine produced is then fortified by the addition of a neutral grape spirit known as aguardente to stop the fermentation, leaving residual sugar in the wine, and to boost the alcohol content. The fortification spirit is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavylium
Pyrylium is a cation (positive ion) with formula , consisting of a six-membered ring of five carbon atoms, each with one hydrogen atom, and one positively charged oxygen atom. The bonds in the ring are conjugated as in benzene, giving it an aromatic character. In particular, because of the positive charge, the oxygen atom is trivalent. Pyrilium is a mono-cyclic and heterocyclic compound, one of the oxonium ions. Salts Pyrylium and its derivatives form stable salts with a variety of anions. Derivatives Many important cations are formally derived from pyrylium by substitution of various functional groups for some or all the hydrogens in the ring. The 2,4,6-triphenylpyrilium, referred to as the Katritzky salt, (after Alan R. Katritzky) is an important example used in many modern examples of metal catalyzed cross-couplings. Chemical properties Like other oxonium ions, pyrylium is unstable in neutral water. However, pyrylium is much less reactive than ordinary oxonium ions beca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yellowish
Varieties of the color yellow may differ in hue, chroma (also called saturation, intensity, or colorfulness) or lightness (or value, tone, or brightness), or in two or three of these qualities. Variations in value are also called tints and shades, a tint being a yellow or other hue mixed with white, a shade being mixed with black. A large selection of these various colors is shown below. Computer web color yellow Yellow (RGB) (X11 yellow) (color wheel yellow) The color box at right shows the most intense yellow representable in 8-bit RGB color model; yellow is a ''secondary'' color in an additive RGB space. This color is also called color wheel yellow. It is at precisely 60 degrees on the HSV color wheel, also known as the RGB color wheel ( Image of RGB color wheel:). Its complementary color is blue. Yellow (CMYK) (process yellow) (canary yellow) Process yellow (also called pigment yellow or printer's yellow), also known as canary yellow, is one of the three colo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxypyranomalvidin-3-glucoside
Vitisin A is a natural phenol found in red wines.Brazilian red wines made from the hybrid grape cultivar Isabel: Phenolic composition and antioxidant capacity. Suzana Lucy Nixdorf and Isidro Hermosín-Gutiérrez, Analytica Chimica Acta, Volume 659, Issues 1-2, 5 February 2010, Pages 208-215, It is a pyranoanthocyanin.Effect of acetaldehyde and several acids on the formation of vitisin A in model wine anthocyanin and colour evolution. Romero C. and Bakker J., International journal of food science & technology, 2000, vol. 35, no. 1, pp. 129-140, See also * Phenolic compounds in wine * Vitisin B (pyranoanthocyanin) Vitisin B is a natural phenol found in red wines.Brazilian red wines made from the hybrid grape cultivar Isabel: Phenolic composition and antioxidant capacity. Suzana Lucy Nixdorf and Isidro Hermosín-Gutiérrez, Analytica Chimica Acta, Volume 65 ... References External links Vitisin A on www.phenol-explorer.eu Pyranoanthocyanins {{aromatic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyranoanthocyanins
The pyranoanthocyanins are a type of pyranoflavonoids. They are chemical compounds formed in red wines by yeast during fermentation processes or during controlled oxygenation processes during the aging of wine. The different classes of pyranoanthocyanins are carboxypyranoanthocyanins, methylpyranoanthocyanins, pyranoanthocyanin-flavanols, pyranoanthocyanin-phenols, portisins, oxovitisins and pyranoanthocyanin dimers; their general structure includes an additional ring (formed between the OH group at C-5 and the C-4 of the anthocyanin pyranic ring) that may have different substituents linked directly at C-10. Examples * Carboxypyranoanthocyanidins, can be considered markers of microoxygenation techniques * Hydroxyphenyl-pyranoanthocyanins * Vitisin A and B * Pinotins * Portosins (vinylpyranoanthocyanins) Vitisin A type * Cyanidin-3-O-glucoside-pyruvic acid (m/z of +H ion:517, λmax 506 nm) * Cyanidin-3-O-acetylglucoside-pyruvic acid (559 - 507) * Cyanidin-coumar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
