Omega-3 nanoencapsulation: casein nanoparticles
Following the development of the encapsulation of docosahexaenoic acid with β-Lg, a whey protein, research was conducted in the Israel Institute of Technology to study the encapsulation of that same hydrophobic nutraceutical with casein protein.
Caseins comprise about 80% of cow-milk proteins and consist of four main proteins: αs1-, αs2-, β- and κ-casein. Caseins are excellent natural vehicles since their biological function is to transport calcium, protein and phosphate from the mother to the neonate. In fact, caseins have a very strong tendency to associate into colloidal particles known as micelles and it was this special feature that inspired the idea of entrapping hydrophobic molecules in casein micelles.
DHA-loaded reassembled-casein micelles were formed according to a method developed previously in this same laboratory, which included the addition of calcium and phosphate. At a 1:1 (caseinate:DHA) molar ratio, stable nanoparticles presented a particle size of 50-60 nm.
A different process was also investigated, where calcium and phosphate were not added, which led to the formation of 90 and 300 nm particles. This system conferred excellent protection to DHA against its degradation.
In conclusion, this research suggested that nanovehicles made of milk proteins, possibly with the addition of polysaccharides, present an innovative technology to enrich non- or low-fat clear beverages with hydrophobic functional ingredients such as DHA, an omega-3 compound of growing relevance in human nutritional needs.
Source:
- P. Zimet, D. Rosenberg , Y.D. Livney. Assembled Casein Micelles and Casein Nanoparticles as Nano-Vehicles for ω-3 Polyunsaturated Fatty Acids. Food Hydrocolloids.
