Professor Kikunae Ikeda of Tokyo Imperial University isolated umami as glutamic acid while studying kombu, giant Japanese sea kelp. He commercialized this finding as monosodium glutamate (MSG), but you need not eat headache powder to taste the wonder (and healthfulness, when organic) of umami. Tomatoes, parmesan, and chicken broth all have high glutamate content. There are also mimics: shiitake mushrooms have umami-like nucleotides that allow them to impart a similar taste.