Wine is a remarkably complex chemical system. Once fermentation begins, hundreds of compounds continuously react, transform and interact with each other. Among them, anthocyanins and other phenolic compounds play a decisive role in determining the colour of red wine – and, ultimately, how consumers perceive its quality.
A new study published in Food Chemistry: X provides an intriguing insight into how cyclodextrins can influence this process [1]. Rather than simply preserving existing wine pigments, cyclodextrins can modify the pathways through which anthocyanins evolve during fermentation and ageing, offering a new way to control wine colour.
Why does wine colour change with age?
The characteristic colour of young red wine is largely associated with anthocyanins extracted from grape skins. Cabernet Sauvignon, for example, contains significant amounts of malvidin-3-O-glucoside and related anthocyanins.
But these molecules do not remain unchanged.
During fermentation and subsequent ageing, anthocyanins undergo a complex series of transformations. They can interact with flavanols, tannins and other phenolic compounds, forming new, often more stable pigment structures such as pyranoanthocyanins and anthocyanin–flavanol adducts.
This chemistry is one of the reasons why the colour of a young red wine can be very different from that of the same wine after several months or years of ageing.
The challenge for winemakers is therefore not simply to obtain a wine with intense colour at bottling. It is to achieve a desirable colour that remains attractive and stable during ageing.
And this is where cyclodextrins become particularly interesting.
What can a cyclodextrin do in wine?
The new study investigated three cyclodextrins: α-cyclodextrin, β-cyclodextrin and hydroxypropyl-β-cyclodextrin (HP-β-CD) were added to Cabernet Sauvignon grape juice before fermentation. The wines were subsequently monitored during 12 months of ageing, with particular attention paid to colour, phenolic compounds and almost 80 anthocyanins and their derivatives.
The result is fascinating: the different cyclodextrins did not behave in the same way.
α-CD: accelerating the formation of stable colour pigments
Among the three CDs, α-CD produced the most pronounced changes.
Rather than simply protecting the original anthocyanins, α-CD appeared to accelerate their transformation into more stable pigment structures.
In particular, the study found increased formation of vitisin-type pyranoanthocyanins and other anthocyanin-derived pigments. These compounds are important because they can contribute to the colour of aged red wine and are generally more resistant to some of the degradation processes affecting the original monomeric anthocyanins.
The α-CD-treated wines showed substantial changes in colour parameters, including increased colour difference and changes in hue and chroma. The effect was particularly pronounced during the first 6–9 months of ageing.
In other words, α-CD appears to act as a kinetic regulator: it does not merely keep anthocyanins unchanged but helps redirect them towards particular products.
Instead of thinking of cyclodextrin simply as a “protective container”, we can begin to consider it as a tool for modulating the reaction network of wine.
β-CD and HP-β-CD: a different strategy
β-CD and HP-β-CD showed a different behaviour.
These cyclodextrins were associated with greater preservation of monomeric and acylated anthocyanins and a more gradual formation of derived pigments. The authors interpret this behaviour as a stabilising or protective effect, in which the cyclodextrin cavity can provide steric shielding for suitable phenolic molecules.
This distinction is important.
α-CD and β-/HP-β-CD may therefore offer complementary approaches:
- α-CD: promote the conversion of unstable anthocyanins into more persistent pigment structures;
- β-CD: slow down pigment transformation and preserve anthocyanins for longer;
- HP-β-CD: provide another form of stabilisation, with its flexible hydroxypropyl substituents influencing molecular interactions.
The choice of cyclodextrin could therefore depend on the desired outcome.
From molecules to the wine in the glass
One of the most interesting aspects of the study is the connection between molecular-level chemistry and the visible properties of wine.
The researchers used a combination of targeted anthocyanin analysis, UV-Vis spectroscopy, CIELAB colour measurements and multivariate statistical approaches to connect individual pigment transformations with the overall evolution of wine colour.
Their results indicate that early-stage wine colour is strongly associated with monomeric anthocyanins, whereas the colour characteristics of more mature wine increasingly depend on higher-molecular-weight derivatives and pyranoanthocyanin–flavanol networks.
Cyclodextrins appear to influence this transition.
This is perhaps the most exciting message of the study: CDs can potentially influence not only how much pigment remains in wine, but also what type of pigment the wine contains as it ages.
And what about wine aroma?
Colour is only one part of the story.
Cyclodextrins have a long history of interaction with volatile and hydrophobic molecules, and their ability to form inclusion complexes makes them particularly interesting for aroma-related applications.
Indeed, previous work from the same research group has investigated cyclodextrins in relation to colour protection, aroma enhancement and sensory improvement of red wines, comparing cyclodextrins with polysaccharides as pre-fermentation additives.
This opens an intriguing broader perspective.
A cyclodextrin-based approach could potentially influence several important wine-quality attributes simultaneously:
phenolic stability → pigment evolution → colour → aroma → sensory perception
Of course, these effects are highly dependent on the cyclodextrin structure, concentration, wine matrix and target compounds. Cyclodextrins should therefore not be regarded as interchangeable additives.
Why this matters for the future of winemaking
The conventional approach to wine technology often focuses on controlling individual parameters—extraction, oxidation, phenolic content, colour or aroma.
The new study suggests that this can be exploited to control the trajectory of wine colour during ageing. And that concept may extend well beyond wine. The same fundamental principle – using cyclodextrin structure to selectively stabilise, protect or redirect molecules – could be relevant to many food and beverage systems in which oxidation, flavour loss, colour instability or undesirable molecular transformations limit product quality.
[1] Liu, C., Wei, X., Zhang, Z., Miao, Q., Prejanò, M., Marino, T., … Li, Y. (2026). Cyclodextrin-mediated improvement of red wine color quality dissected by coloromics and anthocyanin evolution dynamics. Food Chemistry: X, 38, 104199. https://doi.org/10.1016/j.fochx.2026.104199