该研究选取儿茶素、没食子酸、香兰素、槲皮素、山奈酚五种多酚化合物作为辅色剂对紫甘蓝花色苷进行辅色，结果表明随着浓度增加，儿茶素和没食子酸的辅色作用不断加强，当浓度达到0.01 mol/L时，辅色作用增长缓慢；香兰素浓度达到0.004 mol/L时，辅色作用最强，浓度继续增加辅色作用反而减弱；槲皮素和山奈酚对紫甘蓝花色苷的辅色作用较差，当浓度达到0.002 mol/L时加速紫甘蓝花色苷降解。五种多酚化合物中儿茶素辅色作用最好，没食子酸次之，山奈酚和槲皮素较差。儿茶素、没食子酸和香兰素均能显著提高紫甘蓝花色苷的热稳定性，没食子酸对于紫甘蓝花色苷的热稳定性效果最好，将花色苷的降解率从34.02%降低至22.88%，槲皮素和山奈酚对紫甘蓝花色苷的热稳定性影响不大。热力学分析发现，儿茶素、没食子酸和香兰素对紫甘蓝花色苷的辅色作用是自发进行的放热过程，推测辅色作用为非共价结合。因此，儿茶素、没食子酸和香兰素均可以在实际生产中提高紫甘蓝花色苷的热稳定性，其中儿茶素效果最佳。

Five polyphenolic compounds (catechin, gallic acid, vanillin, quercetin, and kaempferol) were selected as co-pigments of purple cabbage anthocyanins. Results indicated that the co-pigmentation effects of catechin and gallic acid strengthened with increased concentration; however, a slow increase rate was observed when the concentration reached 0.01 mol/L. The co-pigmentation effect of vanillin was strongest at 0.004 mol/L but declined when the concentration was further increased. Quercetin and kaempferol exhibited poor co-pigmentation effects and accelerated the degradation of purple cabbage anthocyanin when the concentration of 0.002 mol/L was reached. These results showed that catechin was the most effective co-pigment among the five polyphenolic compounds, followed by gallic acid. Moreover, the thermal stability of purple cabbage anthocyanin was increased significantly by catechin, gallic acid, and vanillin. Gallic acid showed the best enhancement effects on thermal stability, with the degradation rate decreasing from 34.02% to 22.88%, while quercetin and kaempferol had little effects on thermal stability. Thermodynamic analysis revealed that co-pigmentation of purple cabbage anthocyanin with catechin, gallic acid, and vanillin was a spontaneous exothermic process, which suggests that the co-pigmentation effects were caused by noncovalent bonding. Therefore, catechin, gallic acid, and vanillin can be used to enhance the thermal stability of purple cabbage anthocyanins during production, with catechin showing the most promising effect.

江苏省农业科技自主创新资金项目（cx(20)3002）