Ultrasound-assisted extraction of carotenoids from mango (Mangifera indica L. 'Ataulfo') by-products on in vitro bioaccessibility

Mango by-products (peel and paste) are a source of carotenoids, but their bioaccessibility (BA) can be limited by dietary fiber (DF), since it retains these compounds within its structure. The aim of this study was to evaluate the influence of ultrasound-assisted extraction (UAE) on the BA of carotenoids by an in vitro digestion model. The beta-cryptoxanthin (beta Cr) content (3.59 +/- 0.43 mg/g DW) in UAE-peel was higher than that in Control-peel (0.66 +/- 0.03 mg/g DW). The beta-carotene (beta C) content in UAE-peel and UAE-paste was higher than that in Control-peel and Control-paste. The % BA in the UAE-peel improved by 46.93%, 35.21% and 32.62% for beta Cr, Lutein (Lut), and beta C, respectively, compared to that in the Control-peel, and in the UAE-paste, the treatment improved the % BA for Lut, beta Cr, and beta C by 46.04%, 44.16%, and 44.01% respectively, compared with that of the Control-paste. A high percentage of non-bioaccessible beta C was shown for the Control-peel (79.48%) and Control-paste (70.41%), and the percentage was lower in the UAE samples. The released carotenoids were quantified in a kinetic model, and beta-Cr, Lut, and beta C were effectively released in mango UAE-peel. The constant release rate, k, did not show significant differences in both samples. A 2-parameter non-linear regression model was the best fit for the release kinetics. The use of UAE on in vitro digestion conditions noticeably improved the bioaccessibility of carotenoids in mango by-products.