Miso (みそ or 味噌?) is a traditional Japanese seasoning produced by fermenting soybeans with salt and the fungus Aspergillus oryzae, known in Japanese as kōjikin (麹菌?), and sometimes rice, barley, or other ingredients. The result is a thick paste used for sauces and spreads, pickling vegetables or meats, and mixing with dashi soup stock to serve as miso soup called misoshiru (味噌汁?), a Japanese culinary staple. High in protein and rich in vitamins and minerals, miso played an important nutritional role in feudal Japan. Miso is still widely used in Japan, both in traditional and modern cooking, and has been gaining worldwide interest.
Miso is typically salty, but its flavor and aroma depend on various factors in the ingredients and fermentation process. Different varieties of miso have been described as salty, sweet, earthy, fruity, and savory. The traditional Chinese analogue of miso is known as dòujiàng (豆酱).