The museum building was originally constructed as a soy sauce production factory in the early 20th century.
The fermentation barrels on display are made from Yoshino cedar and can stand over two meters tall.
Shodoshima is considered one of the 'four great soy sauce production areas' in Japan due to its specific climate.
The factory uses a traditional brewing method called 'moromi' fermentation, which requires several years to mature.
The museum complex is designated as a Japanese Registered Tangible Cultural Property.
Soy sauce production on Shodoshima dates back over 400 years to the Edo period.
The dark, aromatic atmosphere in the fermentation rooms is due to the presence of yeast and lactic acid bacteria living in the wooden rafters.
The Marukin Soy Sauce Museum is housed within a converted factory building that retains its original wooden architecture and industrial heritage. Located on Shodoshima Island, the facility showcases the traditional brewing processes used to produce soy sauce, a cornerstone of the region's economy. Visitors walk through historical production zones featuring massive cedar barrels, some over a century old. The museum displays antique equipment, including cedar buckets and traditional tools used for fermentation. It is situated on the grounds of the Marukin Soy Sauce company, the largest producer of soy sauce on Shodoshima. The exhibit explains the role of the local climate and the island's water in the fermentation process. A signature feature of the visit is the opportunity to sample soy sauce-flavored ice cream at the on-site shop. The structure itself is a registered Tangible Cultural Property of Japan.
Inside the main fermentation room featuring the towering, dark-stained cedar barrels.
Sample the soy sauce-flavored soft serve ice cream at the shop; it is the museum's most famous culinary offering.
Take time to read the detailed English-language placards, as they explain the complex chemistry behind the brewing process.
Visit the adjacent shop to purchase limited-edition soy sauce varieties not typically found in standard grocery stores.
Do not attempt to walk through the active, restricted factory areas that are not designated as part of the museum path.
Occasionally closed during New Year holidays; check local listings for irregular maintenance closures.
Avoid touching the historic wooden barrels or artifacts, as they are fragile and culturally protected.
