Even though tomatoes are actually fruits, we tend, from a culinary standpoint, to classify them as vegetables. On a global scale, they are the second most important vegetable crop after potatoes. Tomatoes are not just eaten raw, but they are also turned into purées, ketchup, juice, and salsas. Of all the vegetables, they have the greatest content of free glutamate, and it is enhanced when they are prepared in conjunction with other ingredients that contribute synergistic umami, for example, fish and shellfish. This is undoubtedly the reason why tomatoes are so popular and are used in an enormous range of dishes in kitchens all around the world. In fact, tomatoes also have a free nucleotide of their own, adenylate, rendering this popular food ingredient one of the few that can contribute umami synergy on its own.