The effects of gallic/ferulic/caffeic acids on colour intensification and anthocyanin stability.
The mechanism by which copigments stabilize colour, by protecting anthocyanin chromophores from nucleophilic attack, seems well accepted. This study was to determine effects of gallic/ferulic/caffeic acids on colour intensification and anthocyanin stability. Molecular dynamics simulations were applied to explore molecular interactions. Phenolic acids intensified the colour by 19%∼27%. Colour fading during heating followed first-order reactions with half-lives of 3.66, 9.64, 3.50, and 3.39h, whereas anthocyanin degradation, determined by the pH differential method (or HPLC-PDA), followed second-order reactions with half-lives of 3.29 (3.40), 3.43 (3.39), 2.29 (0.39), and 2.72 (0.32)h alone or with gallic/ferulic/caffeic acids, respectively, suggesting that anthocyanin degradation was faster than the colour fading. The strongest protection of gallic acids might be attributed to the shortest distance (4.37Å) of its aromatic ring to the anthocyanin (AC) panel. Hyperchromic effects induced by phenolic acids were pronounced and they obscured the accelerated anthocyanin degradation due to self-association interruption.
Research Center for Food Safety and Nutrition, Key Lab of Urban Agriculture (South), Bor S. Luh Food Safety Research Center, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Bing-Jun
BJ
Qian
College of Resources and Environment Engineering, Yibin University, Yibin, Sichuan 644000, China.
Jian-Hua
JH
Liu
Research Center for Food Safety and Nutrition, Key Lab of Urban Agriculture (South), Bor S. Luh Food Safety Research Center, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Shu-Juan
SJ
Zhao
Research Center for Food Safety and Nutrition, Key Lab of Urban Agriculture (South), Bor S. Luh Food Safety Research Center, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Jian-Xiong
JX
Cai
Research Center for Food Safety and Nutrition, Key Lab of Urban Agriculture (South), Bor S. Luh Food Safety Research Center, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: pjing@sjtu.edu.cn.
Pu
P
Jing
D000872:Anthocyanins / Q000737:chemistry*; D002109:Caffeic Acids / Q000737:chemistry*; D003116:Color; D062385:Hydroxybenzoates; D010936:Plant Extracts / Q000737:chemistry*
D000872:Anthocyanins; D002109:Caffeic Acids; D062385:Hydroxybenzoates; D010936:Plant Extracts; C017616:phenolic acid
Copigmentation; Cyanidin 3-(6″-caffeyl-6‴-ferulylsophoroside)-5-glucoside (PubChem CID: 44256788); Cyanidin 3-(6″-caffeylsophoroside)-5-glucoside (PubChem CID: 44256781); Cyanidin 3-(6″-ferulylsophoroside)-5-glucoside (PubChem CID: 44256782); Cyanidin 3-sophoroside-5-glucoside (PubChem CID: 44256732); Peonidin 3-sophoroside-5-glucoside (PubChem CID: 44256845); Peonidin-3-sophoroside-5-glucoside; Phenolic acid; Purple sweet potato; π-π Stacking