Polysaccharide-induced colloidal stabilization of red wines: Impact on phenolic composition and color characteristic

Polysaccharides play a crucial role in wine quality and colloidal stability. Two types of polysaccharides were applied to three wines with diverse initial phenolic and polysaccharide profiles to evaluate their effects on the color characteristics of the wines. Changes in the colloidal properties, phenolic composition, and color parameters of the wines were analyzed over a one-year bottle aging. The results revealed that the addition of polysaccharides consisting mainly of arabinogalactans (AG) tended to have a higher absolute zeta (ζ) potential value (below −10 mV), indicative of enhanced colloidal stability, while mannoprotein (MP) had little effect. However, the addition of both polysaccharides can influence the colloidal particle size and turbidity of the wines, with distinct variations observed based on the initial matrix composition, especially the polysaccharide content. Furthermore, both polysaccharides promoted the formation and accumulation of anthocyanin derivatives, especially pyranoanthocyanin, while AG had a greater effect, with a maximum increase of nearly 14% compared with the control group at 12 M. The color characteristic of the wines changed accordingly, with a significant increase in the red hue (a∗ value), particularly in wines characterized by low polysaccharide content and high polyphenol level. Notably, the modifications in colloidal properties induced by polysaccharide displayed a significant correlation with polyphenols and color parameters, indicating that a stable colloidal system facilitates color stability. In practical winemaking applications, the addition of polysaccharides should consider factors such as their type, concentration, and the balance of the initial wine composition.