Carotenoid absorption in rats fed with vacuum-fried papaya chips depends on processed food microstructure associated with saturated and unsaturated oils

Abstract

Many studies indicate that food matrix microstructure and type of dietary oil or fat play a key role in carotenoid absorption. Therefore, this work was designed to highlight the relationship between processed food microstructure and carotenoid absorption. This study aimed to evaluate the consumption of a carotenoid-rich fruit snack on lipid profile, glycemia and especially on carotenoid absorption/bioconversion in Wistar rats. Animals were fed with mixtures based on vacuum-fried papaya chips with either soy oil (PC-S) or palm oil (PC-P) during 7 days, receiving 0.29 mg lycopene/kg/day and 0.35 mg total carotenoids/kg/day. Lycopene and retinoids were analyzed in plasma and liver of rats by HPLC-DAD. Results showed that the consumption of mixtures based on papaya chips did not affect the lipid profile or glycemia in rat plasma, regardless the type of oil. Wide-field and confocal microscopy analyses of food matrix helped to understand why lycopene accumulation in the liver was higher (p < 0.05) in rats fed with PC-P (0.442 µg/g liver) than in those fed with PC-S (0.291 µg/g liver). A better dissolution of crystalloid lycopene was found in PC-P. Conversely, a higher bioconversion of provitamin A carotenoids was observed for soy products. The effect of type of oil was underlined by epifluorescence microscopy of papaya mixtures showing homogeneous and small lipid droplets for soy products. These results showed that PC-S could be recommanded as a healthy snack, being a source of provitamin A carotenoids and bioavailable lycopene in a diversified diet.