Industrially scalable complex coacervation process to microencapsulate food ingredients

Microencapsulation by conventional complex coacervation, though highly effective and achievable at the bench-scale, is challenging to scale-up because of the complexity of the process. A novel, industrially-scalable microencapsulation process by in situ complex coacervation during spray drying (the ‘CoCo process’) is introduced, where the multiple steps are collapsed into one, to form dry complex coacervated (CoCo) microcapsules by spray drying. The CoCo process was used to encapsulate d-limonene in CoCo microcapsules using alginate and gelatin as wall materials. Insoluble CoCo particles were produced without chemical cross-linking, with extents of complex coacervation of 75 ± 6% and 64 ± 6% for CoCo particles with and without d-limonene, respectively. Up to 82.7% of d-limonene was retained during spray drying; moreover, the CoCo matrix exhibited excellent barrier properties, retaining up to 80.0% of total d-limonene over 72-day storage in sealed vials at room temperature.