red azuki bean paste or koshian
Rich in plant-based protein and dietary fiber, azuki bean paste provides essential minerals including iron, manganese, and zinc. Due to the refined nature of koshian (with seed coat removed), it has lower fiber content than whole bean preparations but remains a valuable source of complex carbohydrates.
About
Koshian (こしあん) is a smooth, fine-textured Japanese red bean paste made from azuki beans (Vigna angularis), a small legume native to East Asia with dark red to burgundy coloring. The paste is produced by cooking dried azuki beans until tender, then pressing them through a fine sieve to remove the seed coat, and often sweetening the resulting purée with sugar or honey. The term "koshian" literally means "strained bean paste," distinguishing it from chunky variants like tsubuan (whole bean paste). Traditional koshian features a delicate, slightly earthy sweetness with a creamy consistency that ranges from silky to slightly grainy depending on production methods. It is a cornerstone of Japanese wagashi (traditional sweets) and is consumed throughout East Asia in various confectionery and dessert applications.
Culinary Uses
Koshian is fundamental to Japanese and East Asian pastry and confectionery, serving as a filling for mochi, dorayaki (red bean pancakes), and various wagashi such as daifuku, yokan, and anmaki. The paste is also used as a base for beverages (adzuki bean soup), spreads, and ice cream. Its smooth texture makes it ideal for applications requiring refinement and visual elegance. In savory contexts, unsweetened koshian occasionally appears in traditional Asian cuisines as a component in rice dishes or as a binding agent. The paste's neutral yet distinctive flavor profile allows it to pair with both traditional ingredients like matcha and sesame, and modern components such as chocolate and coffee.