Proteosomes based on milk phospholipids and proteins to enhance the stability and bioaccessibility of β-carotene

Abstract

Proteosomes (P) based on milk fat globule membrane's phospholipids (MPs), whey protein isolate (WPI) and sodium caseinate (CasNa) were developed by ultrasonication to encapsulate β-carotene. Entirely milk-ingredients based proteosomes (WPI-MPs-P and CasNa-MPs-P) revealed homogenous distribution with size diameters < 250 nm. WPI-MPs-P depicted positive ζ-potential values (+15.7 ± 0.5 mV), while CasNa-MPs-P demonstrated negative (-32.5 ± 3.4 mV) values of surface charge, respectively and hydrophilic nature of proteosomes was observed by measuring contact-angle (θ). AFM and SEM exhibited spherical to oval and slightly irregular morphology of nanocarriers. For various concentrations of β-carotene, the highest encapsulation efficiency of β-carotene was 90 ± 0.2% and 92 ± 0.8% in WPI-MPs-P and CasNa-MPs-P respectively. FTIR analyses confirmed the hydrophobic and electrostatic interactions-based encapsulation of β-carotene. Beneficial antioxidant-potential of β-carotene was retained after its encapsulation in the proteosomes. Proteosomes increased the digestive-stability (>50%) and bioaccessibility (>85%) of β-carotene. Thus, milk-ingredients based proteosomes offer a novel-strategy to develop functional dairy products to overcome widespread vitamin-A-deficiency.

Keywords: Bioaccessibility; Malnutrition; Milk phospholipids; Milk proteins; Proteosomes; Sustained release; Vitamin A deficiency.