Eggplant's flavor peaks at 42 days.

Spanish food scientists studying the chemistry of eggplant have determined that this purple vegetable tastes best about 42 days after the fruit begins to form. Rosa M. Esteban and colleagues at the Autonomous University of Madrid tracked the acidity and chemical content of three varieties, analyzing them at days 5, 11, 15, 28, 42, and 54.

In the June Journal of Agricultural and Food Chemistry, they report finding little difference among the three types. But in all three, they observed that sugar content declined during the second week of growth, then increased up through the end of the sixth week, and finally dropped dramatically during the next 10 days. The amount of ascorbic acid and of phenols - important flavor compounds - also increased dramatically through the 42nd day, then dropped precipitously Thus, they conclude that the eggplant reaches its most delectable state after six weeks.