Enhanced color stability in blueberry-grape blended fruit wines: Insight into synergistic copigmentation of epigallocatechin gallate and ferulic acid

The significant anthocyanin loss in blueberry wine can lead to color degradation during aging. This study showed that blending blueberries with 'Cabernet Sauvignon' grapes notably enhanced acylated anthocyanins and copigmentation levels, delaying the decrease in the copigment anthocyanin ratio and significantly increasing the polymerized anthocyanin ratio over time. A model blueberry wine system was applied to evaluate the copigmentation effects of primary copigments from grapes on anthocyanins. The thermodynamic parameter analysis and molecular docking showed that epigallocatechin gallate (EGCG) exhibited superior copigmentation effects compared to other compounds. Additionally, the copigmentation effects of EGCG and ferulic acid (FA) together were more pronounced than those of EGCG alone, suggesting a synergistic enhancement of copigmentation. These findings provide valuable insights for the blueberry wine industry, indicating that blending techniques and the use of composite copigments can significantly enhance color stability.