Which substance is responsible for the taste sensation marked in blue?

Taste sensation marked in purple denotes Umami taste. 1. Sweet Taste (Pink): sugars, glycols, alcohols, aldehydes, ketones, amides, esters, some amino acids, some small proteins, sulfonic acids, halogenated acids, and inorganic salts of lead and beryllium 2. Salty Taste (Purple): cations of the salts, especially sodium cations 3. Sour Taste (Green): approximately propoional to the logarithm of the hydrogen ion concentration 4. Bitter taste (Yelllow): Long-chain organic substances that contain nitrogen and alkaloids 5. Umami (Blue): Umami, a Japanese word meaning "delicious," designates a pleasant taste sensation. Umami is the dominant taste of food containing L-glutamate, such as meat extracts and aging cheese.