A tulaberry was 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 asked Quark to negotiate a contract for tulaberries with 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")