Spray-drying microencapsulation of CoQ10 in olive oil for enhanced water dispersion, stability and bioaccessibility: Influence of type of emulsifiers and/or wall materials

Abstract

There is increasing interest in developing food-grade coenzyme Q10 (CoQ10) ingredients for functional food formulations. This paper reported a spray-drying microencapsulation of CoQ10 (in olive oil) using different food-grade biopolymers [soy protein isolate (SPI), pea protein isolate (PPI), defatted milk powder and octenylsuccinic anhydride-modified starch (OSA)] as the emulsifiers and wall materials, with the aim to improve its water solubility, stability and bioaccessibility. To improve the microencapsulation, maltodextrin (with a dextrose equivalent value of 16) was blended with the emulsifiers to produce the spray-dried microencapsulates. The type of proteins affected their physicochemical characteristics, including particle size, surface hydrophobicity and ξ-potential, which accordingly led to the differences in characteristics of the formed emulsions, e.g. droplet size and distribution profile, flocculated state of droplets, stability against coalescence and creaming, as well as interfacial protein concentration. All the microencapsulate preparations exhibited high encapsulation efficiency and good redispersion and/or dissolution behavior, though the encapsulation efficiency and dissolution behavior varied with the type of applied emulsifiers. The better encapsulation efficiency and dissolution behavior were largely related to the higher interfacial emulsifier concentration of the corresponding original emulsions. Furthermore, the microencapsulation remarkably improved the UV- or heat- stability, as well as the in vitro bioaccessibility of CoQ10. The improvement also distinctly varied with the type of applied emulsifiers. The results suggest that the spray-drying microencapsulation is an effective technique to improve the low water solubility and bioavailability of CoQ10, however, the choice of emulsifiers or wall materials is important for the optimization of the CoQ10 encapsulation.