Extraction of methyl xanthines and their UHPLC–DAD determination in consumable beverages used in E astern province of S audi A rabia

Coffee and tea are the most widely consumed beverages worldwide. However, the consumer may be unaware of the exact amount of methyl xanthine (MX, i.e. caffeine [C], theobromine [TB] and theophylline [TH]) consumed, as most of the products do not list the proper amounts. This may lead to serious risks including cardiovascular, kidney and stimulant effects. The aim of the study was to determine the MX amount in ready‐to‐use beverages (coffee and...