Crabtree negative organisms such as Kluyveromyces, Pichia, Hansenula and Candida, are used to make selected organic products such as lactic acid. The organisms are cultured in a first culture medium that includes glucose, under conditions that promote cellular respiration. The organisms are then cultured under a second set of conditions that promote production of the selected organic product. The organisms preferably contain an exogenous lactate dehydrogenase gene.