Physicochemical properties of muffins prepared with lutein & zeaxanthin-enriched egg yolk powder

Designing functional foods relies not only on incorporating bioactive compounds into a formulation but also on their ability to remain useful within the product. In this study, lutein and zeaxanthin (L&Z)-enriched egg yolk powder (EEYP), sourced from hens fed with Dunaliella tertiolecta mp3, was incorporated as a functional ingredient in muffins. Two formulations were prepared: with butter (EEYP-B) and butter-free (EEYP-BF). The color and texture of the muffins and the thermal stability and bioaccessibility after simulated digestion of the carotenoids were assessed. The results indicated that the physical properties of the muffins were not influenced by the L&Z addition. Moreover, L&Z in EEYP-B were less heat labile than in EEYP-BF and control samples with degradation rates of 10–12%, 15–17%, and >20%, respectively. Surprisingly, the bioaccessibility of L&Z in the EEYP-BF muffins was higher than in the control and butter-containing samples after digestion. As a result, enriching a daily product with L&Z was proved successful at increasing its carotenoid content after baking, evidencing also that the butter-free formulation exhibited the highest bioaccessibility.