Tulaberry

From Memory Alpha, the free Star Trek reference.

A tulaberry is a blue fruit native to the Gamma Quadrant and the main ingredient in tulaberry wine.

In 2370, Grand Nagus Zek explained to Quark that tulaberries were the key to establishing a Ferengi presence inside the Gamma Quadrant and sent Quark on a mission to acquire tulaberry wine from the Dosi. However, Zek later admitted that he was using the tulaberry trade to learn the secret of the Dominion, which he believed was the true key to profit in the Gamma Quadrant. (DS9: "Rules of Acquisition")

In 2377, when helping Seven of Nine decorate her quarters, Neelix suggested a Talaxian mosaic in tulaberry blue, with an orange inlay. (VOY: "Human Error")