Effect of time and light on the total phenolic compounds and antioxidant capacity of ready-to-drink matte and white tea beverages

Abstract

Teas are rich in compounds with antioxidant properties that must be preserved in drinks made from their extracts. In this study, the stability of total phenolics compounds (TPC) and the antioxidant capacity (AC) were evaluated in ready-to-drink mate and white tea formulations in the flavors of natural, lemon and peach. The drinks were stored for 8 weeks in amber bottles or exposed to light, at room temperature, with analyzes performed every 2 weeks. The TPC content of formulations with mate tea in the dark and exposed to light remained stable during storage. For the white tea formulations exposed to light, a drop of 24 to 31% in TPC levels was detected at the end of storage. There was a substantial drop in AC evaluated by FRAP, in all tea formulations, after 2 weeks of storage, in the absence and presence of light. Small changes in the AC of the beverages evaluated by ABTS were observed in the dark, while in the light there was a drop of 31 to 44% for mate and white teas, respectively. Ready-to-drink teas, even if filled in amber packaging, were not stable in terms of the potential for iron reduction. However, the content of TPC and AC detected by ABTS were preserved. The phenolic compounds and AC for the formulations based on white or mate teas, are preserved as long as the drinks are filled in amber bottles at room temperature for a maximum of two weeks.