Changes in composition of the lipid matrix produce a differential incorporation of carotenoids in micelles. Interaction effect of cholesterol and oil

Efficiency of the micellar incorporation of carotenoids was determined through the application of an in vitro digestion procedure, and in function of the composition of the lipophilic environment, where digestion was carried out. Analysed factors affecting micellization level were presence of oil in the digestion mixture, class of pigment, and cholesterol. The addition of oil to the digestion mixture caused changes of different extent in function of the class of pigment, and significant interactions between the factors presence of oil and class of pigment were detected. Accessibility of lycopene was affected negatively by an increase of the amount of vegetable oil, while Intent, ester increased its presence in micelles. Although cholesterol was not a significant factor affecting the micellization efficiency, when cholesterol and oil were added to the digestion process, the amount of micellarized pigment was significantly affected, positively or negatively depending on lipophilic characteristics of the pigment. Therefore, an interaction between the factors cholesterol and presence of oil with different effects on the micellization of pigments was analysed. The physical-chemical differences of carotenoids, that are consequence of their structural features, generated diverse requirements of the lipophilic environment to facilitate their emulsion and subsequent incorporation into micelles. (c) 2007 Elsevier Ltd. All rights reserved.