Episode Details

Every year, Tokyo authorities warn people to cut their mochi into small pieces, because the chewy rice cake sends more than 100 people to the hospital in the city alone. This episode explains what makes mochi different, starting with mochigome, a glutinous short-grain rice that is almost entirely amylopectin. Its branched starch molecules trap water and form a stretchy, chewy gel, and the result stains red rather than blue in an iodine test. Early farmers deliberately bred the waxy gene mutation behind it.

We trace mochi's spiritual history: homemade production in the Kofun period, the Bungo no Kuni Fudoki legend of mochi turning into a white bird, Heian rituals for newborns and newlyweds, and samurai kagami mochi that was broken with a wooden mallet rather than cut. Sugar brought by Portuguese traders turned it into a sweet, and we cover the rhythm of mochitsuki pounding, the 62°C temperature factories must reach, seasonal sweets like sakura mochi, and global versions like mochi ice cream, mochi donuts and tangyuan.

• Why mochigome's amylopectin gives mochi its stretchy texture
• Mochi in Japanese folklore, Shinto ritual and samurai tradition
• How Portuguese sugar turned mochi into a sweet
• Traditional mochitsuki pounding and modern factory production
• Choking hazards, seasonal varieties and global mochi desserts