Kinetics of Malvidin‐3‐Glucoside Condensation in Wine Model Systems

Abstract

Wine model systems containing equlmolar quantities of malvidindglucoside and d-catechin, with and without acetaldehyde, were stored anaerobically at 22, 32, 42, and 52°C. Malvidind-glucoside and d-catechin disappearance and polymer appearance were monitored by HPLC and calorimetric methods. Reaction rates and activation energies were calculated. The malvidin3glucoside and d-catechin condensation reactions showed pseudo fist order kinetics both with and without the presence of acetaldehyde. However, activation energies were not significantly different.

First confirmation in red wine of products resulting from direct anthocyanin-tannin reactions

“…The resulting colourless adduct can then be converted into the correspondinḡ avylium salt (ref form). However, a second hypothesis may be envisaged, for which Mv3g would be linked by its C-4 position 2,9,11 and directly released by thiolysis as a cationic anthocyanin, which would be unable to react with the nucleophilic thiol reagent. In fact, when Mv3g was submitted to thiolysis conditions, it did not react with toluene-a-thiol and remained in cationic form.…”

Detection and Partial Characterisation of New Anthocyanin-Derived Pigments in Wine

“…Two major reaction pathways have been postulated. The first one involves the formation of acetaldehyde bridges between anthocyanins and flavanols (Singleton et al 1964;Timberlake and Bridle 1976;Baranowski and Nagel 1983). The second reported pathway consists in direct condensation of anthocyanins with flavanols, yielding yellow-orange pigments (Somers 1971;Liao et a1 1992).…”

“…Sixteen anthocyanins, including the 3-glucosides of delphinidin, cyanidin, petunidin, peonidin and malvidin, their acetic and p-coumaric esters, and caffeic ester of malvidin-3-glucoside have been reported in Vitis uinifera varieties (Wulf and Nagel 1978;Bakker and Timberlake 1985). The occurrence of condensation reactions between various flavanols and malvidin-3-glucoside, the major pigment in all V uinifera varieties, or malvidin-3,5-diglucoside, found in non-uinifera Vitis species, has been studied in model systems (Timberlake and Bridle 1976;Baranowski and Nagel 1983;Liao et al 1992). Acetaldehyde-linked products have been obtained in solutions containing malvidin-3-glucoside and catechin (Timberlake and Bridle 1976;Baranowski and Nagel 1983) and partly characterised by mass spectrometry (Archier 1992).…”

“…The occurrence of condensation reactions between various flavanols and malvidin-3-glucoside, the major pigment in all V uinifera varieties, or malvidin-3,5-diglucoside, found in non-uinifera Vitis species, has been studied in model systems (Timberlake and Bridle 1976;Baranowski and Nagel 1983;Liao et al 1992). Acetaldehyde-linked products have been obtained in solutions containing malvidin-3-glucoside and catechin (Timberlake and Bridle 1976;Baranowski and Nagel 1983) and partly characterised by mass spectrometry (Archier 1992). However, given the bathochromic shift resulting from conversion of grape anthocyanins ( A, , , 540 nm) to these molecules ( A, , , 548 nm), they are more likely to participate in the colour of young red wines than to account for the tile-like orange-red of mature wines.…”

Efecto De La Adición De Copigmentos Sobre La Composición Fenólica De Vinos Tintos De Tempranillo Elaborados Con Diferentes Técnicas De Vinificación

“…Las reacciones de copigmentación han sido estudiadas en soluciones modelo, encontrándose que intervienen en ellas algunos compuestos del grupo de los ácidos hidroxicinámicos y de los flavonoides, que actúan sobre la coloración de los antocianos, en distintas condiciones de pH, temperatura y concentraciones de copigmento y de antociano, dando lugar a un aumento en la intensidad del color (efecto hipercrómico) y un desplazamiento de la longitud de onda a la cual se produce el máximo de absorbancia (efecto batocrómico) (Baranowwski y Nagel, 1983;Brouillard et al, 1989;Bloor y Falshaw, 2000). En algunos de estos estudios se ha investigado y precisado el mecanismo de reacción y la constante de estabilidad del complejo formado entre el antociano y el copigmento.…”