4.Conclusion The present study demonstrated that green, white and black tea extracts were effectively employed for production of polyphe nol fortified yogurt with antioxidant properties Green tea extract has the highest content of polyphenols and antiokidant activity followed by white and black tea extracts respectively These tea extracts positively affected the phenolic content in yogurt during 21 days of refrigerated storage, 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. However, all tea yogurts showed high antioxidant activity compared to plain yogurt during 21 days of addition, black tea yogurt showed the lowest antioxidant activity among the others. Since tea is a natural herbal product with therapeutic and nutritional properties; green, white and black teas are all strongly recommended as a novel ingredient to enhance yogurt's antioxidant properties as a new functional food. Further study will be needed to examine the consumer sensory evaluation and viability of probiotics of all the three types of tea yogurt.
Acknowledgement
We acknowledge the financial support of University of Malaya Research Grant (RG023-090BIO)