Copigmentation and enological parameters were studied in a collection of 250 red wines. Although several copigmentation studies have been performed with model solutions, little is known about the actual consequences directly in wine of anthocyanin interactions. To date, some studies have considered relationships between copigmentation and natural wine constituents, but none correlates copigmentation measurements with the real wide concentration in wine. In this work, published hypotheses based on model solutions such as phenolic acid copigmentation ability or the influence of copigmentation factors such as flavonols are empirically evaluated in a large sample of wines for the first time. The study confirms previous results obtained from solutions, whereas other factors suggested as being relevant seem to be unrelated to the studied effect at the concentration range naturally occurring in the wines studied. For instance, the important role of flavonols and hydroxycinnamic acids has been ratified, whereas ethanol, gallic acid, and some metals show significant inverse correlations with copigmentation. Unexpectedly, magnesium content in wine correlates with color, whereas the concentration of traditional copigments, such as quercetin, does not show any correlation with copigmentation.

Chromatic characteristics and their relationships with copigmentation and phenolic composition were studied in 160 bottled red wines. Free anthocyanins, copigmented anthocyanins and polymeric pigments contributing to color were calculated according to Boulton protocol and related to main changes produced in wine visible spectra after destroying any copigmented anthocyanins effect. Color differences between copigmented and non copigmented wines were quantified and related with ageing, cultivar and phenolic profile. Phenomenon of co-pigmentation visually increases the colour at 420, 520 and 620 nm for most of wines. Copigmented wines showed a mean value of 8.26 CIELab units higher than non copigmented (ΔE ab(cnc) ), being this shift deeper for young wines than for aged wines. Copigmentation mostly changed hue and decreased L, a* and b* values therefore resulted into purplish and darker wine. Visual variations in color caused by copigmentation was related to particularly anthocyanins and copigments (mostly flavonols and hydroxycinnamic acids).

No abstract

No abstract

Wines from the Atlantic Islands of Macaronesia come from unusual terroirs due to their volcanic soils and the tropical and subtropical climatic conditions from this region. Some of these Islands produce highly appreciated fortified wines traded around the world since the sixteenth century, such as Madeira or Canary. Nowadays their distinct winemaking techniques and sweet wine traditions combine with the production of table wines. Previous studies described peculiar properties in wines from these regions, mostly related with their phenolic content and color, which are particularly important in the less produced red wines. The main purpose of this chapter is to characterize red wines produced in the Atlantic Islands of Macaronesia in terms of oenological and physicochemical properties. Wines from these islands are extremely atypical, as their climates conditions are exceptional and red grape cultivars are exclusive. Furthermore, specific viticulture techniques are applied in these latitudes to proportionate the unique characteristics outlined in this work. Original experimental data from 300 red wines produced in 8 Atlantic islands from Canary and Cape Verde archipelago and an important reviewing study for Azores and Madeira red wines are considered herein. Results are presented according to archipelago.