5. Microencapsulation methods for fragrances

5.1 General strategy

With a few exceptions, the starting point is almost always an oil-in-water emulsion, in which the fragrance acts as the oil phase. The fragrance is emulsified either pure or diluted in an olfactory-neutral oil, such as a fatty acid ester. This phase is generally liquid, although in some cases the perfume is solidified in the form of particles or micro-(nano)gels.

The emulsion is generally stabilized by one or more polymers with emulsifying properties. These polymers are also known as colloidal stabilizers or protective colloids. Examples include modified celluloses, polyvinyl alcohols, acrylates, block or non-block copolymers, etc. Stabilization using nanoparticles to form so-called Pickering emulsions has recently come back into vogue....