Titanium Dioxide Nanoparticles Do Not Adversely Impact Carotenoid Bioaccessibility from Tomatoes Consumed with Different Nanoemulsions: In Vitro Digestion Study.

Abstract

Titanium dioxide (TiO2) is used as an additive to whiten some foods and beverages that contain lipid nanoparticles. We therefore investigated the combined influence of TiO2 and lipid nanoparticles on carotenoid bioaccessibility from tomatoes. TiO2 nanoparticles ( d = 167 nm) were combined with nanoemulsions ( d ≈ 150 nm) stabilized by various emulsifiers: Tween 80, whey protein, or sodium caseinate. The mixed systems were then mixed with tomatoes and passed through a simulated gastrointestinal tract (GIT). The emulsifier type significantly influenced carotenoid bioaccessibility ( p < 0.05), mainly because of differences in the ability of the emulsifier-coated lipid droplets to extract carotenoids from tomatoes and form mixed micelles. TiO2 addition did not impact lipid digestion and carotenoid bioaccessibility ( p > 0.05). These results suggested that carotenoid bioaccessibility was not influenced by TiO2 addition but did depend on the type of emulsifier used to stabilize lipid nanoparticles.