Determination of Caffeine Content at the Difference in Arabica and Robusta Coffee Roast Levels Using HPLCI. Farikha A, L. Eka, Ngatinem, A. Rahayuningtyas and B. UlumBIO Web Conf., 158 (2025) 04011DOI: https://doi.org/10.1051/bioconf/202515804011