β-cryptoxanthin encapsulated nanoliposome in milk with an approach to enhance vitamin A through fortification

Vitamin A deficiency (VAD) can result in harmful physiological effects on health across diverse populations, highlighting the need for alternative solutions to address this global issue. This study investigates the stability of β-cryptoxanthin, a provitamin A carotenoid encapsulated in nanoliposomes, in fortified milk, along with the physicochemical properties of this fortified milk aimed to target VAD. Prior to fortification, fluorescence spectroscopy confirmed the encapsulation of β-cryptoxanthin within the hydrophobic membrane of the nanoliposome, with a peroxide value of 0.74 ± 0.04 mEq/kg, indicating its strong oxidative stability. Up to >90% cell viability of the Human embryonic kidney cells was observed in presence of up to 100 μg/mL of the fortificant (β-cryptoxanthin encapsulated nanoliposome). Fortified milk retained its nutritional composition, including fat, protein, dry sedimentation, specific gravity, and colour (p > 0.05). Following fortification, minor increase in viscosity (p > 0.05) and slight decrease in electrical conductivity (p > 0.05), from 4.55 ± 0.05 to 4.41 ± 0.03 mS/cm, was observed. Additionally, >92% of β-cryptoxanthin was retained after heat treatment (63 °C for 30 min, 72 °C for 15 s, and 135 °C for 3 s), confirming the thermostable nature of the fortified milk. The fortified milk showed a significant increase in ferric-reducing antioxidant capacity, from 196.02 ± 0.16 to 548.57 ± 1.23 μmol/L (p < 0.01), while lipid peroxidation decreased from 0.40 ± 0.02 to 0.29 ± 0.05 mg malondialdehyde/L (p < 0.01). Protein carbonyl concentration was also reduced (p < 0.01), from 0.95 ± 0.07 to 0.62 ± 0.02 nmol/mg, protecting milk proteins against oxidation. About 17%–48.32% of the recommended dietary allowance for vitamin A was obtained from fortified milk under simulated conditions, addressing VAD challenges.