Catechin and epicatechin are types of flavan-3-ols, a class of flavonoids, which are phenolic compounds found abundantly in various foods and beverages, including tea, cocoa, and certain fruits. These compounds are known for their antioxidant properties, contributing to the prevention of oxidative stress-related diseases. Catechins are colorless and have a bitter taste, which can influence the flavor profile of foods and beverages. They play a significant role in the astringency of tea and the bitterness of chocolate. The structural difference between catechin and epicatechin lies in the stereochemistry at the 3rd carbon, affecting their bioavailability and biological activity. These compounds are slightly soluble in water, highly soluble in alcohol, and insoluble in fats, which influences their extraction and use in food processing.