Milk in tea: exploring the chemistry and biological activities

Tea is a widely consumed beverage worldwide. Many countries have a daily practice of consuming black tea with milk. There has been an increase in the popularity of adding tea to dairy products. This review summarizes the effects of adding milk to tea on biological activities, the relationship between the polyphenols of tea and milk, and the possible applications of tea polyphenols in the dairy industry. Tea with milk has different health benefits than tea without milk, as it has been proven that proteins and polyphenols can have a strong interaction, which can decrease the availability of tea polyphenols. Milk proteins have the ability to transport and absorb catechins from tea through the digestive system. Consumers highly desire the maximum uptake of antioxidants from tea and proteins in milk without negatively impacting tea flavor. The relationships between milk protein and tea polyphenols could be favorably used in the dairy industry.