홍국쌀 is made by fermenting white rice with the mold Monascus purpureus, which produces a distinctive deep red to purple coloration throughout the rice grains. It has been used for centuries in East Asian cuisine as both a food colorant and a flavor ingredient in dishes such as Peking duck, char siu pork, and fermented tofu.
홍국쌀 contains naturally occurring pigments including monascin, ankaflavin, and monascorubramine, as well as the compound monacolin K. In the food industry, it is available as whole fermented grains or as a fine powder for direct incorporation into formulations. It is valued for its natural origin, excellent color stability in processed foods, and growing consumer recognition as a traditional ingredient.