geranial

Instead, three compounds in particular — geranial, 2-methylbutanal, and 3-methyl-1-butanol — contribute to the sweetness of tomatoes, at least.

Geranial, Klee concluded, somehow improves a tomato's overall flavor, perhaps by enhancing the fruit's innate sweetness.

Supporting this reasoning, a majority of taste testers in an earlier study enjoyed the flavor of tomatoes engineered to contain lemon basil geraniol, which is related to geranial.

In contrast, a less prevalent volatile compound named geranial made a huge difference to tomato flavor.

Klee noticed that many of the tomatoes the taste testers preferred contained moderate to high levels of geranial.