Formation and characterization of microcapsules by complex coacervation with liquid or solid aroma cores

• Published in: Flavour and fragrance journal 2009-01, Vol.24 (1), p.17-24
• Main Authors: Leclercq, Segolene, Harlander, Kristin R, Reineccius, Gary A
• Format: Article
• Language: English
• Subjects: Acacia; Aroma and flavouring agent industries; Biological and medical sciences; coacervation; encapsulation; flavour; Food industries; Fundamental and applied biological sciences. Psychology; storage stability
• ISSN: 0882-5734; 1099-1026
• DOI: 10.1002/ffj.1911

The process parameters typically reported in the literature for the encapsulation of aroma compounds via coacervation are reviewed and their effects on capsule formation discussed. We then report on our approach to produce coacervates [liquid (limonene or medium chain triglycerides) or solid core (menthol)] using gum acacia/gelatin as wall materials. Manufacturing parameters were optimized to allow the production of consistent batches of coacervate microcapsules. Capsules were cross-linked with glutaraldehyde and freeze-dried. Coacervates were characterized for their structure and shape, size distribution, flavour load and water uptake rate. In addition, a brief storage study compared the ability of coacervate capsules and spray-dried capsules (using modified starch as carrier material) to protect limonene from oxidation. No detectable increase in limonene oxide could be detected in capsules made by coacervation over 25 days in storage at 45 °C, whereas a significant increase in limonene oxide was detected in spray-dried powder over the same period. Encapsulation by coacervation (as described in this paper) appears to be an effective technique for encapsulating aroma compounds and provides a good barrier against oxidation of sensitive material. Copyright © 2008 John Wiley & Sons, Ltd.