Fish oil alginate-chitosan beads made with Prosopis alba exudate gum showed the highest protection against lipid oxidation and resistance to appearance changes, according to findings published in Food Chemistry.
“[T]he encapsulation of fish oil in alginate-gum-chitosan beads allows obtaining a stable functional ingredient able to be used for the fortification of low moisture content food products such as powdered juices, instant formulae to prepare soups, bakery products, sauces, among others,” wrote ingredients from Universidad Nacional del Chaco Austral, Universidad de Buenos Aires, and the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET).
“Present results allow considering Prosopis alba exudate gum, as a novel excipient to improve oils protection in alginate beads, with the added benefits of employing an undervalued natural resource.”
Immobilization on alginate beads is inexpensive and easy to do, explained the researchers, but there are disadvantages of the system, including large pore size, erosion and low retention capacity. In order to improve these basic alginate-calcium systems, formulators have looked to combine alginate with other hydrocolloids such as chitosan, pectin, and cornstarch.
For the new study, the Argentina-based researchers tested the effects of Prosopis alba exudate gum on alginate-chitosan encapsulates containing fish oil. Results showed that the mesquite gum increased the hygroscopicity of the encapsulates.
This was a consequence of a “higher oil retention in the inner structure, which leaves more hydrophilic sites available and a higher hydrocolloid fraction exposed at beads surface”, explained the researchers.
“[E]ncapsulates containing [Prosopis alba exudate gum] showed the highest protection against lipid oxidation and chromatic or appearance changes.
“These results allow considering Prosopis alba exudate gum, as a novel excipient to protect fish oil encapsulated in low moisture polyelectrolyte systems, with the added benefits of employing an undervalued natural resource,” they concluded.
Source: Food Chemistry
Published online ahead of print, doi: 10.1016/j.foodchem.2018.01.018
“Impact of Prosopis alba exudate gum on sorption properties and physical stability of fish oil alginate beads prepared by ionic gelation”
Authors: F.E. Vasile et al.