This study for the first time compares the in vivo (response in serum from individuals of
an interventional study) and in vitro effects (bioaccessibility determined from simulated
gastrointestinal digestion) of two plant sterol (PS)-enriched milk-based fruit beverages (with
and without tangerine fruit juice rich in β-cryptoxanthin (β-Cx)) in order to assess their suitability
as PS-enriched food matrixes, and the possible interactions between the two bioactive
compounds (β-Cx and PS) that might affect their absorption. The randomized, doubleblind,
crossover study (performed in 36 postmenopausal women) showed the β-sitosterol
and campesterol serum concentrations after four weeks of consumption of the beverages
(1.5 g PS/day) to increase significantly (ranging 1.6–2.4 g/mL and 0.3–0.4 g/mL, respectively),
thereby confirming suitability as matrices for PS-enrichment. The results therefore
indicated similar behavior of PS supplied by these beverages and evaluated through in vitro
or in vivo assays, independently of whether the samples contained β-Cx or not.