In recent years, the interest in dietary antioxidants and bioactive compounds, mainly found in vegetables, has prompted research in the field of new polyphenol-rich drinks. The aim of the present work was to design new beverages using lemon juice and maqui (Aristotelia chilensis), rich in flavonoids and vitamin C. The composition of the new beverages as well as their compounds stability, antioxidant capacity and phenolic content over 70 days of storage period were studied. Results showed how anthocyanins and other phytochemicals from maqui preserved vitamin C and other flavonoids in the new mixtures owing to a higher rate of anthocyanin degradation. However, for the colour characteristics, the CIELab parameters displayed only slight variations, and the samples presented attractive colour during storage. The new beverages also had high values of in vitro antioxidant capacity, mainly owed to the maqui polyphenols, with a strong stability throughout study. Therefore, a new designed drink for the growing market of high nutritional and health-promoting food products has been developed.