Effect of oxygenation on polyphenol changes occurring in the course of wine-making

Phenolic Composition, Antioxidant Capacity and in vitro Cytotoxicity Assessment of Fruit Wines

“…In addi tion, the pigment analysis of the strawberry wine conducted earlier showed a signifi cant decrease of anthocyanin content aft er fermentation, where only 3-9 % of anthocyanins present in fruits were retained, as well as their progressive decrease throughout the storage (40). Specifi cally, the decrease of free anthocyanins, due to the formation of pyranoanthocyanins, ethyl-bridged compounds and derived pigments, occurs during wine ageing (47). Therefore, the composition and stability of strawberry antho cyanins based on pelargonidin-3-glucoside as the predominant anthocyanin, followed by pelargonidin-3--rutinoside and cyanidin-3-glucoside (45) is probably responsible for these results, as well as their interactions with other phenolic compounds occurring during winemaking and ageing.…”

Micro-Oxygenation and Fining Agent Treatments: Impact on Color of Moroccan Red Press Wine

“…In this work we used the same chromatic measurement procedure described in the previous work [2,16]. Absorbance measurements were made with a SAFAS UV mc2 spectrophotometer (Monaco) and color indices were deduced from these absorbance measurements.…”

“…These reactions released more complex and stable anthocyanin derived pigments, such as various pyranoanthocyanins, polymeric anthocyanins produced from condensation between anthocyanin and/or flavan-3-ols directly or mediated by aldehydes. Such variations can result in the significant changes of the color [2,8,22]. The monitoring of total anthocyanins and the polymeric pigments parameter during the storage (Figure 2) showed a drop of total anthocyanins, and an increase of polymerized pigments.…”

“…Anthocyanins and their derivatives are the crucial pigments responsible for the red wine color. During wine aging, the concentration of monomeric anthocyanins declines constantly, while numerous more complex and stable anthocyanin derived pigments are formed [2]. It is usually supposed that these pigments are formed by direct condensation between anthocyanin and/or flavan-3-ols or by a aldehyde-mediated condensation resulting in oligomeric and polymeric pigments, sometimes referred to as pigmented polymers.…”

“…It is usually supposed that these pigments are formed by direct condensation between anthocyanin and/or flavan-3-ols or by a aldehyde-mediated condensation resulting in oligomeric and polymeric pigments, sometimes referred to as pigmented polymers. Some authors have shown that anthocyanins can react as well with metabolites of the two successive fermentations including pyruvic acid, vinylphenol, glyoxylic acid, giving rise to a new family of anthocyaninderived pigments, namely, pyrano-anthocyanins [2][3][4]. The color of wine is mainly assessed by spectrophotometric measurements that are converted into typical indexes claimed to reflect the composition and concentration of anthocyanins and polymeric pigments.…”