Complex sentence: The "nuruk" is mixed by hand with hard-boiled rice and placed in a liquor jug with water for about 15 days, by which time its color is yellowish, and it has a savory taste.
Split into simpler sentences: The "nuruk" is then mixed by hand with hard-boiled rice and placed in a liquor jug with water for about 15 days. After this time its color is yellowish, and it has a savory taste.