Copigmentation evidence of phenolic compound: The effect of caffeic and rosmarinic acids addition on the chromatic quality and phenolic composition of Cabernet Sauvignon red wine from the Hexi Corridor region (China)

Although phenolic copigments are rarely colored, they can still influence color expression in red wine copigmentation. Here, prefermentative agents, such as caffeic and rosmarinic acids, were added as copigments during Cabernet Sauvignon red winemaking. The evolution of colors and polyphenols was analyzed by tristimulus colorimetry and high-performance liquid chromatography-tandem mass spectrometry during brewing and aging periods. The results showed that the addition of caffeic and rosmarinic copigments was beneficial to obtain more saturated and vivid hue of wines. The changes in color were correlated with a significant increase in anthocyanins concentration. Moreover, the results demonstrated that the addition of the two phenolic copigments increased the concentration of total phenols and enhanced the copigmentation effect, indicating improved chromatic intensity and color stability of wines. Therefore, the addition of caffeic and rosmarinic acids is a simple and useful enological technique to obtain red wines with high color quality and aging potential.