7.3. Tailoring the ingredients to suit its application

In many cases, an encapsulated ingredient that is appropriate for a particular food product can be selected from among those that are already available commercially. In some instances, however, it may be necessary to customise the properties of the microcapsules to fit the product. This work, undertaken by both suppliers of encapsulated ingredients and custom encapsulation services, is based on information provided by the food technologist.

Before considering the properties desired in the encapsulate, the propose for encapsulation must be clear:

- Is it to change the form of the product from a liquid state to a dry form?
- Is it to provide controlled release?
- Is it to improve stability? Improve flowability?
- Is it to reduce dusting?
- Is it to separated incompatible ingredients?

Various properties of microcapsules, which may be changed to suit specific ingredient applications, include their composition, mechanism of release, particle size, final physical form, and cost. Some of the questions listed below may be helpful in defining these.

• What functionality must the encapsulated ingredients provide to the finished product?
• What coating material is nonreactive with both the ingredient to be encapsulated and the formulation to which the encapsulate will be added?
• What processing conditions must be encapsulated ingredient survives before releasing its contents?
• What is the optimum concentration of the reactive core material in the encapsulated?
• By what mechanism will the ingredient be released from the microcapsule; e.g., agitation? pH? pressure? solubility? temperature? time?
• Are there any special forms of release required; e.g., sustained release or delayed release?
• What are the particle size, density, and stability requirements for the encapsulated ingredient?
• What is the desired form of encapsulate; e.g., power or compressed granules?
• What are the cost constraints of the encapsulated ingredient?