Copigmentation Effect of Some Phenolic Acids on Stabilization of Roselle (Hibiscus sabdariffa) Anthocyanin Extract

摘要

The present study aimed at utilization of copigmentation phenomenon to increase the stability of anthocyanin in roselle extract during storage at 10°C for 60 days by the addition of some phenolic acids (ferulic, cinnamic and coumaric) as a copigments and investigate the possibility of using copigmented extracts as a natural food colorants instead of harmful synthetic ones. The data obtained confirmed that addition of the aforementioned phenolic acids to roselle anthocyanin extracts resulted in an increment of anthocyanin and color stability during storage comparing with the control extract. At the end of storage period, the reduction in anthocyanin content were 31.53, 20.48, 9.31 and 5.52% for control and extracts copigmented with ferulic, cinnamic coumaric acids respectively. Addition of phenolic acids to roselle extract also attributed to a hyperchromic effect and bathochromic shift in visible absorption spectra of copigmented extracts compared to the control. Roselle anthocyanin extracts treated with phenolic acids showed a noticeable antioxidant and antimicrobial activities compared with control extract. Marshmallow prepared from studied copigmented roselle extracts as a natural colorants was highly accepted by panelists.