Abstract
Miso, a traditional Japanese fermented food, contains metabolites derived from the fermentation of raw materials by “koji” （Aspergillus oryzae）, yeast （Saccharomyces）, or lactic acid bacteria. The secondary metabolites in miso may vary depending on the manufacturing process of the materials. In this study, we focused on sea salt made from “Kaitei-yukaisui”, spring sea water found in seabeds. This sea salt is characterized by its lower concentration of NaCl（75 ％）, but complemented by other minerals such as MgCl2, MgSO4, CaSO4, or KCl that come from bittern. On days 111 and 181 of the miso ripening process with this sea salt, the usual seasalt （＞95 ％ NaCl）, or a 1:1 mixture of both, were extracted and analyzed using LC-MS for their metabolites. As a result of multivariate analysis on the LC-MS data obtained, the secondary metabolites varied depending on the type of sea salts used. It is believed that the balance of NaCl or other minerals might affect the fermentation process by “koji” and/or yeast in miso.
