Cosmetics
Here the two important factors tend to be the anti-oxidant protection of the shell coupled with the ability of the finger or thumb to release an encapsulated liquid onto the skin.
The active ingredient is spread over the surface of the skin over a period of time by continued rubbing. However, depending on the encapsulation process a continuous diffusion from the exines (that act as a reservoir) can be achieved.
The encapsulated ingredients form a dry powder, which can be added to a cream or lotion. Several different powders can be used in a single product so for example, sun screen, sun tan and an aroma could be present in a sun lotion. The colour of the powder can be varied from chocolate-brown to light cream depending upon the application for which it is required.
Where the active ingredient is volatile a co-encapsulating substance is required to block the pores in the exine shell or to form an inner or outer protective layer. In order to obtain effective release on application however, this substance must be easily broken or able to be pushed out. One possibility is cocoa butter which can easily be applied as a liquid during the filling procedure. It then becomes solid at ambient temperatures, but melts again when put on the skin. Rubbing will release both the cocoa butter and the active ingredients it is helping to contain.
