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Fruit beverages are a source of antioxidants which are often commercially supplemented with milk, vitamins and/or minerals to improve their nutritional value and provide bioactive food components. We tested the hypothesis that these fruitt beverages protect against oxidative stress damage in Caco-2 cells. A fruit beverage (grape+orange+apricot) (with/out milk and/or iron/zinc) was submitted to in vitro gastrointestinal digestion, and soluble fractions were incubated with Caco-2 cultures. Oxidative stress was induced with 5 mM H202. Intracellular reactive oxygen species (ROS), mitochondrial membrane integrity (MMI) and cell cycle progression were analyzed by flow cytometry to assess oxidative injury. Mitochondrial enzyme activity and intracellular glutathione (GSH) were also measured. Exposure to H202 increased ROS and decreased GSH content, indicating oxidative stress. Preincubation with fruit beverage soluble fractions reduced oxidative stress injury. Lower ROS levels were deteted in cultures preincubated with Fe and Zn containing samples versus others without mineral addition. Addition of milk to the beverage protected MMI and mitochondrial enzyme activity compared to the beverage without milk. In preincubated cultures G1 cell proportion was not altered, no other variations on cycle were detected. These results show that these beverages exert a cytoprotctive effect on epithelial cells. [ABSTRACT FROM AUTHOR]