Fig. 6
From: The history and science of Chongkukjang, a Korean fermented soybean product
]. Meju did not exist in China; for a long time, it was written using the Chinese characters as jangkuk (醬麴) (a). At the time, the mold involved in the fermentation process of meju (Aspergillus) was correctly written as mold (kuk, 麴). This suggests that even during this period, Koreans were able to distinguish between bacteria (gyun, 菌) and mold. In Hunmongjahoe (a), the word si clearly refers to Chongkukjang, while 醬麴 refers to myeoju (meju). However, from the 1600s, when Chongkukjang began to be recorded as 戰國醬, 靑局醬, 淸麴醬, or 煎豉醬, the character si (豉) as instead used to refer to meju or sometimes doenjang. Doenjang was another food that did not exist in China. This is why the same word was used to refer to meju and doenjang. There are a number of references to meju in ancient comments. It is called myejo in Yeosaseoseonhae (女四書諺解, 1737) (b), or called myojo in Uihwi (宜彙, 1871) (c), Junbosallimkyongje (增補山林經濟, 1766), Yeoyudangjeonseo (與猶堂全書, 1762–1836) and Mulmyeonggo (物名攷, 1820), and referred to as myeoju/myoju in Jaryujuseok (字類註釋, 1856) (d) and Jajeonseokyo (字典釋要, 1909)