ABSTRACT. The carotenoid content and profile evolution of Uruguayan Tannat grapevine fruit was studied. Two differently managed vineyards exposed to different sunlight and temperature conditions were sampled over two successive ripening periods. Seven carotenoids were identified by HPLC-DAD:neoxanthin, violaxanthin, luteo-xanthin, lutein 5,6-epoxide, flavoxanthin, lutein, and ?-carotene. Irrespective of species, the highest carotenoid concentrations were found at initial sampling, immediately decreasing sharply to a minimum at harvest. However, a different variation was found for each carotenoid. Whereas significant carotenoid degradation was observed in both vineyards, the effect was greater in grapes of vines growing in mulched soil. The evolution of carotenoid breakdown products was also studied by GC-MS-SIM. In fruit from the mulched vineyard, the norisoprenoid content increased noticeably (by 85% of the initial concentration) over the ripening season, whereas no such increase was found in fruit from the conventional vineyard. © 2010 by the American Society for Enology and Viticulture. All rights reserved.