The Recognition and Role of Umami

The role of umami as a basic taste should perhaps also be seen in a wider context. The recognition of umami as a basic taste quality produced by glutamate and ribonucleotides may be only one example of the responsiveness of the taste system to amino acids generally. The taste system may be both more broadly receptive and more flexible when it comes to biologically important compounds. As one example, animals fed a diet deficient in just one essential amino acid will recognize its presence in foods, consuming those foods preferentially.²² This suggests that the taste system is responsive to metabolic needs to the extent that it can create a temporary “basic taste” by becoming sensitive to a required nutrient to fulfill the need. Similarly, studies of malnourished children have shown the addition of an otherwise unpalatable amino acid mixture can increase the consumption of a soup,²³ suggesting increased palatability. These effects disappeared when the nutritional state returned to normal. Glutamate, by contrast, improved the palatability of the soup in these subjects, but this effect was not responsive to nutritional state, a fact in keeping with its status as a non-essential amino acid.