The present study investigated the effect of green, white or black tea (Camellia sinensis) on the
fermentation of milk and antioxidant potential of yogurt during 21 days of storage at 4
C. All yogurts
were analyzed for total phenolic content (TPC), identification of phenolic compounds and antioxidant
potential using diphenyl picrylhydrazyl radical scavenging (DPPH), ferric reducing antioxidant power
(FRAP) and ferrous ion chelating (FIC) assays. Green tea yogurt showed the highest phenolic content
(p < 0.05) followed by white tea yogurt and black tea yogurt. LCMS/MS analysis revealed the absence of
several phenolic compounds in tea yogurts, despite their presence in tea water extracts, as well as the
presence of new phenolic compounds. All tea yogurts showed higher (p < 0.05) FRAP and FIC values than
respective control during 21 days of storage. However, BTY showed the lowest values of DPPH scavenging
activity and FRAP during storage period. In addition, the antioxidant activity for all tea yogurts remained
almost constant over storage period. In conclusion, green, white and black tea can be successfully
employed to improve the antioxidant properties of yogurt and provide sustained antioxidants during
storage.
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