Other authors employed ionic gelation
to encapsulate active compounds by other techniques like
internal gelation or absorption method. A promising alternative
was proposed by Chan, Yim, Phan, Mansa, and Ravindra (2010).
They encapsulated an herbal aqueous extract in calcium alginate
beads using the absorption method, and found that this technique
gave a 2–6 times higher encapsulation efficiency than the
direct extrusion method. Stojanovic et al. (2012) used electrostatic
extrusion and improved the encapsulation loading of thyme
extract by about 16% in comparison to the absorption method.
They eliminated the driving force for diffusion by maintaining
the same concentration of polyphenolic compounds in the gelling
solution as within the gel matrix. The incorporation of a filler
material into alginate matrix is another strategy for solving the
above mentioned disadvantages. Starch has been employed to
increase the probiotic bacteria entrapment (Sultana et al., 2000).
Rassis, Saguy, and Nussinovitch (2002) found that values between
10 and 30% of corn starch reduced calcium alginate shrinkage.