Abstract
Edible films based on chitosan were prepared, with
and without basil or thyme essential oils, with the aim of
assessing their protective ability against lipid oxidation and
their antimicrobial activity. Chitosan films had good oxygenbarrier
properties, which were worsened by essential oil addition,
especially when the film equilibrium moisture content
increased. Due to the oxygen-barrier effect, all the films
effectively protected pork fat from oxidation, in comparison
to unprotected samples. In spite of the worsening of the
oxygen-barrier properties, the films with essential oils were
more effective than those of pure chitosan, which points to the
chemical action of specific antioxidant compounds of the oils.
Films were effective to control microbial growth in minced
pork meat, although the incorporation of essential oils did not
improve their antimicrobial activity. Throughout the storage,
the films led to colour changes in minced pork meat associated
with the conversion of myoglobin into metmyoglobin due to
the reduction of the oxygen availability.
