Hydrocolloid capsules

Phase separation process takes advantage of the phenomenon called polymer- lymer incompatibility. The process utilizes two polymers that are soluble in a common solvent yet do not mix with one another in the solution. The polymers form two separate phases one polymer intended to form the capsnle walls, the other incompatible polymer meant to induce the separation of the two phases, but not meant to be part of the capsule wall material. This process is somewhat related to the complex coacervation process. The phase separation process is considered as the oldest true encapsulation technology first developed by the National Cash Register Company for carbonless copy-paper. Microencapsnlation by coacervation involves the phase separation of one or more hydrocolloids from the initial solntion, and the subseqnent deposition of the newly formed coacervate phase around the active ingredient suspended or mnulsified in the same reaction media. The size of the miCTocapsules formed may be in the range of 10-250 pm. 

Peniche C., Howland I., CarriUo O., Zaldivar C., Argtielles-Monal W., Formation and stability of shark liver oil loaded chitosan/calcium alginate capsules, Food Hydrocolloids, 18(5), 2004, 865-871. 

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