On-line monitoring of stevioside sweetener hydrolysis to steviol in acidic aqueous solutions

► The aim of this study was to investigate acidic hydrolysis of Stevia by ESI-MS. ► Aqueous solutions of stevioside at different pH values were monitored in real time by direct infusion ESIMS. ► Fast hydrolysis of the stevioside molecule to steviol in aqueous acidic solutions was observed, particularly in acidic juices.