Release and absorption of carotenes from processed carrots (Daucus carota) using in vitro digestion coupled with a Caco-2 cell trans-well culture model

The release and absorption (bioavailability) of carotenoids is a prerequisite for their nutritional impact. This can be strongly affected by the processing conditions used to prepare the food matrix that contains them. To determine the effect of processing on carotenoid bioavailability, homogenized, raw, blanched and cooked carrots were exposed to an in vitro gastric and intestinal digestion model. Final digest samples were placed onto a Caco-2 cell trans-well monolayer culture to mimic intestinal absorption. The results show that the cooked carrot puree consisting of primarily single plant cell particles had the highest release of carotenes, followed by blanched consisting primarily of plant cell clusters and raw carrot puree consisting of larger plant cell clusters. Absorption through the Caco-2 cell layer was the highest from the digesta of cooked carrot puree followed by the digesta of blanched carrot puree. This study demonstrates that thermal processing and/or mechanical homogenization to disrupt plant cell wall matrix enhances the in vitro bioavailability of carotenes from carrots.