Changes in Vitamin C, Phenolic, and Carotenoid Profiles Throughout in Vitro Gastrointestinal Digestion of a Blended Fruit Juice

The aim of this research was to evaluate the influence of an in vitro gastrointestinal digestion on the stability and bioaccessibility of vitamin C, phenolic compounds, and carotenoids, as well as the antioxidant activity in a blended fruit juice (BFJ) containing orange, pineapple, and kiwi. Vitamin C and most of the analyzed phenolic compounds were quite stable under gastric conditions (recovery > 75%), whereas carotenoids diminished significantly (to 64%). The concentration of all the evaluated compounds decreased during small intestinal digestion. The bioaccessibility of hydrophilic constituents was higher than that of lipophilic constituents. Flavonoids, vitamin C, and phenolic acids showed bioaccessibilities of 20.1, 15.0, and 12.7%, respectively. However, carotenes and xanthophylls were around 7.6 and 17.4% available for absorption. Despite the decrease in the concentration of these bioactive compounds after being subjected to an in vitro gastrointestinal digestion, results suggest that BFJ is an important source of bioaccessible constituents.