Roasting-Dependent Changes in Antioxidant Activity and Metabolite Profiles of Coffea liberica: Unraveling Bioactive Compounds and Their Functional Properties

Coffea liberica, despite its high antioxidant activity reported in the green bean, has had limited research in the literature on changes in metabolite profiling across different roasting levels. Therefore, the objective of the present study was to evaluate the antioxidant activity and metabolite profiling of the green beans and various roasting levels of Coffea liberica brew using multiple antioxidant assays namely (total phenolic content, total flavonoid content, 1,1-Diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power, 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), and hydrogen peroxide scavenging activity) and liquid chromatography mass spectrometry coupled with quadrupole time-of-flight (LC/MS-QTOF), respectively. Notably, light-roasted coffee brew retained the highest antioxidant activity across most antioxidant assays. A total of 95 significant metabolites were identified, encompassing different classes of compounds such as phenolic acids, flavonoids, amino acids, alkaloids, heterocyclics, organic acids, and others. Chlorogenic acid derivatives, flavonoids, and alkaloids were the significant key metabolites (pCoffea liberica brew across different roasting conditions. These findings demonstrate that light-roasted coffee brew has the potential to enhance the formation and alteration of bioactive compounds that may provide health benefits, thereby highlighting it as a potential source of natural food that is beneficial to health.