Gelatin-based encapsulation matrices were produced from
food-grade ingredients without the need of employing high temperatures
or toxic solvents by electrohydrodynamic treatment of
gelatin solutions in diluted acetic acid. The electrospraying process
was initially optimized in order to obtain neat particles, almost free
of fibrils, to facilitate handling and dispersion into food products.
Pseudo-spherical particles with mean sizes in the submicron range
were obtained. The potential of these particles to be used as edible
carriers for the encapsulation and protection of a model, watersoluble
antioxidant, EGCG, was tested by producing electrosprayed
gelatin particles with a theoretical antioxidant loading of
10% w/w. Infrared spectroscopy and ABTS$þ assays revealed that theencapsulation efficiency of the systemwas very close to 100%, much
higher than that reported for other encapsulation systems for the
protection of catechins. Moreover, the radical scavenging assays
proved that encapsulation by the e-spraying technique did not
damage the bioactive compound, as it retained its antioxidant activity
intact. Additionally, this work also proved that the obtained
gelatin capsules were capable of stabilizing EGCG against degradation
in aqueous solution (pH ¼ 7.4), as its antioxidant activitywas
better preserved in this media when encapsulated than in its free
form. This stabilization can be attributed to both the delay of its
dissolution in aqueous media, as observed in the in-vitro EGCG
release assays, and to the intermolecular interactions which were
established between the active molecule and its encapsulating
matrix. The overall results presented in this work demonstrate, for
the first time, the potential of electrosprayed gelatin particles to be
used as encapsulation matrices for polyphenols with application in
the development of functional foods.