Contents of chlorogenic acids and caffeine in various coffee-related products.

Coffee is the most popular beverage in the Republic of Korea, other than Korea's traditional green tea. Coffee contains many physiologically active substances, such as chlorogenic acids (CGAs) and caffeine. Previous studies have focused on the content of CGAs and caffeine in brewed coffee.

Determination of chlorogenic acids and caffeine in homemade brewed coffee prepared under various conditions.

Coffee, a complex mixture of more than 800 volatile compounds, is one of the most valuable commodity in the world, whereas caffeine and chlorogenic acids (CGAs) are the most common compounds. CGAs are mainly composed of caffeoylquinic acids (CQAs), dicaffeoylquinic acids (diCQAs), and feruloylquinic acids (FQAs). The major CGAs in coffee are neochlorogenic acid (3-CQA), cryptochlorogenic acid (4-CQA), and chlorogenic acid (5-CQA).