In 1908, Tokyo Imperial University biochemist Kikunae Ikeda refused to accept that humans could only taste sweet, salty, sour, and bitter. Obsessed with the savory depth of dashi, he extracted and crystallized the compound in kombu kelp, turning roughly 40 kilograms of seaweed into about 30 grams of glutamic acid, and named the new sensation umami.

This episode follows Ikeda from lab bench to industry: testing glutamate salts until sodium glutamate proved the most soluble and palatable, patenting the process, and partnering with the Suzuki brothers in 1909 to launch Ajinomoto. We also cover how MSG production evolved, why it pairs so powerfully with ribonucleotides, and what double-blind studies and toxicology data reveal about the Chinese restaurant syndrome panic.

• How Ikeda connected glutamic acid, first identified by Karl Heinrich Ritthausen in 1866, to a human taste receptor
• Why monosodium glutamate beat calcium, potassium, ammonium, and magnesium glutamate as a seasoning
• Three eras of manufacturing: acid hydrolysis of wheat gluten, synthesis from acrylonitrile, and modern bacterial fermentation
• How disodium inosinate and disodium guanylate amplify umami by helping glutamate bind longer to the receptor
• What blinded capsule trials, the 1995 FASEB report, and LD50 comparisons with table salt say about MSG safety