Nuruk

Nuruk (Korean: 누룩) is a traditional Korean fermentation starter. It is used to make various types of Korean alcoholic beverages including takju, cheongju, and soju. It is an essential ingredient in shindari and is mixed with rice. Historically, it was used in a variety of provinces of Korea, including Jeju Island. Wheat, rice (of both the glutinous and non-glutinous types), and barley are used to make nuruk, either as whole grain or in the form of grits or flour. Wheat nuruk is the most common variety. The dry grain is moistened, shaped into a large cake, and hung up to ferment for 2‒4 weeks in an ondol room. The cake matures at a precise temperature until a mold forms.