To compare the in vitro bioaccessibility of lutein, zeaxanthin,
-cryptoxanthin, lycopene, and
-and
-carotenes from relevant dietary contributors, a gastrointestinal model was used to assess the stability,isomerization, carotenol ester hydrolysis, and micellarization. Salivar, gastric, duodenal, and micellarphases were extracted, with and without saponification, and analyzed by using a quality-controlledHPLC method. The stability of carotenoids under digestion conditions was >75%, regardless of thefood analyzed, whereas micellarization ranged from 5 to 100%, depending on the carotenoid andthe food.
cis-Isomers were maintained in processed foods, but increased in fresh foods. Xanthophyllester hydrolysis was incomplete (<40%), and both free and ester forms were incorporated intosupernatants, regardless of the xanthophyll involved and the food assessed. In vitro bioaccesibilityvaries widely both for different carotenoids in a given food and for a given carotenoid in differentfoods. Although in vitro bioaccesibility may not be enough to predict the in vivo bioavailability, it maybe relevant for the food industry and for food-based dietary guidelines.