Photodegradation of rosé wines: Effects of controlled irradiation

Rosé wines, may suffer quality losses due to exposure to light (color degradation and undesirable flavors and aromas. In this work, an irradiation equipment was used to simulate light exposure of rosé wines and to study its influence on color and compounds involved in photodegradation reactions. Riboflavin degraded rapidly under light, following first-order kinetics, with a kinetic constant of 0.0125 min^-1 and a half-life of 55.4 min. After 16 h of irradiation, color intensity and CIELAB coordinate a* were reduced by 14 % and 18 %, respectively, and total anthocyanin content showed losses of 26 %. Interestingly, methionine levels did not decrease and concentrations of volatile sulfur compounds remained below sensory thresholds throughout the study. However, sensory analysis confirmed a decline in wine quality with increased light exposure. These findings suggest that anthocyanins may have reacted with riboflavin rather than methionine, thus playing a protective role by slowing riboflavin degradation and preventing the formation of volatile sulfur compounds. Therefore, rosé wines with low color and, therefore, low anthocyanin content, are more sensitive to photodegradation. This highlights the need to develop photoprotection strategies to preserve rosé wine quality.