Essential oil, matrix microencapsulation, REM
Protecting and drying hydrophobic substances
Essential oils, carotenoids, flavors or even hydrophobic plant substances are challenging candidates in terms of formulation and process due to their chemical structure. Such substances are usually extremely sensitive to oxidation and to higher temperatures. For many applications, these substances are needed in solid formulations, for example in flavored teas and dessert mixes or as essential oils, neutral in taste and stable over time as additives in baby food.
The microencapsulation process combines the inclusion of hydrophobic substances in a matrix with granulation and drying.
In the first process step, the oil is emulsified and encapsulated with an encapsulation material that protects against oxidation – such as modified starches, hydrocolloids or even proteins. Stabilization of the emulsion has a decisive influence on product quality. It prevents the microcapsules from being destroyed in the subsequent process. The contents of the capsules thus remain protected from oxidation.
Fluid bed technology and spouted bed technology are particularly suitable for drying at moderate product temperatures. The latter scores with shorter residence times. Both technologies enable the production of compact granules. The reduction of the surface area and the dense matrix reduce the attack surface for oxygen and improve the long-term stability. The use of nitrogen as a process gas enables further optimization of product quality. As with all spray granulation processes, the particle size of the end product is freely adjustable.
The variety of process variants within fluid bed and spouted bed technology offers the whole spectrum from drying to controlled release of active ingredients.
At the Glatt Technology Center in Weimar, we work with you to determine the optimum process conditions for your product in feasibility trials for product development. Various laboratory facilities and comprehensive analytical equipment are available for this purpose. On our pilot plants, we optimize the process and scale it up reliably to a stable and economical production scale. The results from this form the basis for the design and construction as well as the erection of your fluid bed or spouted bed plant, tailored to your requirements. As an alternative to our own process technology, we offer you the outsourcing of your production by means of contract manufacturing at Glatt.
Further information on this topic can also be found in the following publications: