SIGNATURE WORK
CONFERENCE & EXHIBITION 2022

Folin-Ciocalteu (F-C) method has been widely applied in the determination of total phenolic compounds (TPC) in plants and plant-based products. However, the Folin-Ciocalteu procedures are rarely analyzed and modifications to the standard Folin-Ciocalteu method may not be validated in the quantitative standards. Pomegranate is one common type of fruit that is rich in phenolic substances. In this research, a thorough study on the Folin-Ciocalteu method in terms of the basification orders, kinetics, and changing variables of juice concentrations and Folin-Ciocalteu Reagent (FCR) concentrations was conducted on the pomegranate juice. The results showed that the Folin-Ciocalteu reaction was rapid in the first minute and was stable after 30 minutes. Simple mathematical models were proposed for the kinetics of the Folin-Ciocalteu reactions with prior basification as a mix of first-order reactions. The phenolic contents obtained in the assays with late basification were above 50% higher than the phenolic contents obtained in the assays with prior basification in terms of absorbance at 760 nm, which highlighted the significance of the order of addition of sodium carbonate. In addition, adequate FCR was required to optimize the determination of TPC.