Evaluation of Biofunctional Compounds Content from Brewed Coffee

Abstract

Coffee, one of the most popular beverages worldwide, is an infusion of ground, roasted coffee beans. Today, coffee is considered a functional food, especially due to its high content of compounds that exert antioxidant and other beneficial biological properties. The annual consumption exceeds 5 billion kilograms of coffee, which corresponds to 500 billion cups. The aim of the present study was to evaluate the content in total phenolic compounds, flavonoids, caffeine as well as the antioxidant activity of three brewed coffee samples in order to assess the amount of these bioactive compounds in a cup of coffee. The quantification of total phenolic compounds was achieved by Folin-Ciocalteu method, while the flavonoids content was determined using a chromogenic system of NaNO2-Al(NO3)3-NaOH based spectrophotometric method. The caffeine was extracted from brewed coffee samples with dichlormethane and then was quantified by measuring the absorbance of the extract at 260 nm. The antioxidant capacity of each coffee sample was assessed by evaluating their radical scavenging activity on DPPH radical. Even though Arabica coffee variety is appreciated for its fine aroma profile, Robusta variety has proved to be richer in phenolic compounds, flavonoids and caffeine. The larger amount of compounds with antioxidant properties found in Robusta brewed coffee was also confirmed by the obtained antioxidant capacity values.