Microencapsulation/Granulation The Essence of Efficiency: Microencapsulation Contains the Power of Essential Oils
Microencapsulation of essential oils by spray granulation using spouted bed technology – Essential oils contain the power of nature. To use this power companies aspire to modern process technology. This is because the microencapsulation in closed cycle mode ensures highquality products as well as an efficient production process.
Essential oils are volatile substances that are susceptible to oxidation and light. They change or can even lose their properties when coming into direct contact with the environment. Till now, these phytochemicals have found numerous uses and applications. For protection and easier handling, as well as for better dosing and targeted release properties, these substances are increasingly offered and used by various industries in an encapsulated and often freeflowing form.
Several chemical and physical processes are available for encapsulation. One key physical method is the microencapsulation by spray granulation in a spouted bed process. Using a matrix containing oil-in-water emulsion as a starting material, the spray granulation yields solid particles of defined size in which the oil has been very finely distributed in an optimal way.
Typical Problems With Microencapsulation...
The inclusion of a liquid within a solid matrix inevitably increases the moisture of the particles and with that their tendency to agglomerate. This makes a trouble-free application of traditional fluidized bed processes difficult.
These encapsulation problems can be avoided with the continuous spouted bed technology developed by Glatt Ingenieurtechnik. Furthermore, owing to the thermodynamic equilibrium conditions present in a spray granulation process, a certain part of the oil to be encapsulated escapes from the granulation zone along with the fluidizing air.
This has two drawbacks; first, a considerable part of the active substances is lost in the production process, and second, the permissible legal limits for volatile organic substances in industrial exhaust gases being exceeded.
...and How to Avoid Them
Usually, oil-containing granules are produced in a commonly used single-pass system. For different volatile oils, the processing parameters with the highest impact were determined by sensitivity analysis for those systems.