Kojis

Kojis are a traditional Japanese fermented food product made from fish, typically small, oily fish such as mackerel, sardines, or anchovies. The fermentation process involves salting the fish and allowing them to age in a controlled environment, often for several months to a year. This process not only preserves the fish but also enhances their flavor, creating a rich, umami-packed ingredient. Kojis are commonly used in Japanese cuisine, particularly in dishes like *karaage* (fried chicken), *karaage don* (fried chicken donburi), and *karaage sando* (fried chicken sandwiches), where they add depth and complexity to the sauce.

The preparation of kojis begins with cleaning and salting the fish, which is then left to ferment in a cool, dry place. The fermentation process develops a strong, savory aroma and a dark, almost black color, distinguishing them from fresh fish. In addition to their culinary use, kojis have been historically valued for their nutritional benefits, as fermentation increases the bioavailability of certain nutrients, such as omega-3 fatty acids and B vitamins.

Kojis are also known for their role in Japanese *umami* cuisine, where fermented and aged ingredients are prized for their deep, savory taste. While they are most commonly associated with Japanese cooking, their use has spread to other cuisines, particularly in East and Southeast Asia. However, their strong flavor and distinct texture make them a niche ingredient, often reserved for those familiar with fermented foods.

Modern commercial production of kojis has made them more widely available, though traditional methods remain popular among purists. They are typically sold in jars or cans, preserved in their fermented brine. When used in cooking, they are often blended into sauces or marinades, where their intense flavor can be balanced with other ingredients. Despite their acquired taste, kojis continue to be a beloved component of Japanese culinary tradition.