Discover Japan's culinary culture with a look at the history and manufacturing of soy sauce in the town of Yuasa. According to legend, a 13th century Zen Buddhist monk discovered soy sauce by accident here while making kinzanji miso, a type of bean paste. At its height in the 17th century, Yuasa boasted 90 soy sauce factories but only four remain today. One of the most prosperous is Yuasa Soy Sauce Ltd., which makes soy sauce traditionally by hand. During the tour of the facilities you'll discover how soy sauce is brewed with "koji," an enzyme needed to break down starch into sugars and turns proteins into amino acids. Although fermentation techniques came from China between the 6th and 9th centuries, Japan quickly developed its own unique processes. Next, experience Yuasa's charms with a walking tour through the Yuasa Machigoto Soy Sauce Museum.