Red (Rice) Miso Koji Starter for red rice Sendai Miso (6-12 months to age), and sweet red Edo Miso (4-6 weeks to age) All starters come with detailed instructions and recipes. One starter makes 6 pounds of koji for misos. This is a TWO PART FERMENTATION. Making koji, the first step, mixes cooked grains and/or soybeans with different strains of Aspergillus oryzae, a mold, called "tane koji" or koji starter. This first step involves cooking the grain, adding the starter, and incubating the koji culture about 48 hours. The second fermentation, making amazake, misos, shoyu, or tamari involves simply stirring the koji together with other ingredients according to the directions provided.