Flavor encapsulation alginates

Szente, L. and J. Szejtli, 1988. Stabilization of flavors by cyclodextrins. In Flavor Encapsulation, S.J. Risch (ed.), pp. 148-157. ACS Symposium Series 370, Washington DC American Chemical Society. Tpnnesen, H.H. and J. Karlsen, 2002. Alginate in drug delivery systems. Drug Dev. Ind. Pharm., 28 621-630. 

Alginates, unique hydrocolloids extracted from selected species of brown seaweed (kelp), interact with calcium ions to produce thermally stable gels. Using this interaction, flavor oils may be encapsulated or entrapped in the algin gel matrix. Encapsulation is accomplished at ambient temperatures. Products may be used "as is" (wet) or subsequently dried. This technique offers the potential for novel flavor effects, flavor protection, and new food products. 

Because of their ability to react with calcium ions at ambient temperatures to form thermally stable gels or fibers, alginates can provide a useful encapsulating or entrapping system for oil soluble flavor compounds. 

Although alginate encapsulation or entrapment of oil soluble flavors is quite different from traditional encapsulation methods, it could serve as a valuable tool for liquid systems where a protective effect, delayed release, or combination texture/flavor effect is needed. 

In complex coacervation (20 pm to 1 nun), for example, aqueous solutions of active component (AC), polyanion (-) and polycation (+) are mixed. The two polymers with opposite charges (electrostatic interactions) will interact to form a deposit of coacervate at the surface of AC (i.e., acacia gum, alginate CMC with gelatine proteins and anionic polysaccharides) (De Kruif et al., 2004). Reticulation may be provoked by dilution, and modification of pH, tanperature (Figure 39.10). Gelatine and acacia gum (opposite charge at low pH) were used to encapsulate flavor lipophilic oil to be used in frozen foods and released upon heating (Yeo et aL, 2005), with liquid or solid core (Leclercq et al., 2009). 

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