- Tannic acid: This is the most abundant polyphenol in tea and is responsible for its astringent, bitter taste. Tannic acid can bind to proteins in saliva, creating a dry, puckery sensation in the mouth.

- Caffeic acid: This acid is found in both black and green tea and has antioxidant and anti-inflammatory properties.

- Chlorogenic acid: This acid is found in higher concentrations in green tea and has been linked to several health benefits, including weight loss and improved blood sugar control.

- Gallic acid: This acid is found in both black and green tea and has antioxidant and anti-cancer properties.

The type and concentration of acids in tea can vary depending on the type of tea, the growing conditions, and the processing method.