Episode Details

For generations, scientists insisted the tongue could detect only sweet, sour, salty and bitter. In 1908, Tokyo chemistry professor Kikunae Ikeda studied a simple bowl of kombu dashi and isolated glutamate, the compound behind a savory taste he named umami.

This episode follows Ikeda from the lab to the founding of Ajinomoto and the launch of MSG, then tracks the discoveries of inosinate and guanylate that explain umami synergy. We look at why it took until 1985 for umami to gain scientific recognition, how receptors on the tongue and in the gut were identified in the 2000s, and what umami means for nutrition, elderly appetite and sodium reduction today.

• How ancient foods like Roman garum and fermented soy sauces were packed with glutamate long before chemistry
• Why cooking, aging and fermentation unlock free glutamate from otherwise tasteless proteins
• The founding of Ajinomoto in 1909 and what the FDA and double blind studies say about MSG safety
• How glutamate combined with IMP and GMP multiplies savory flavor, from dashi to Parmesan on tomato sauce
• The discovery of TAS1R1 and TAS1R3 umami receptors and their role in the gut-brain axis