To improve the quality and extend the shelf-life of chicken breast, Whey Protein Isolate (WPI) edible
coatings with oregano or clove essential oils (EOs) incorporated as natural antimicrobials have been
developed. These insoluble, homogeneous and continuous WPI coatings formed an imperceptible second
skin covering the chicken breast. The antimicrobial effect of the coatings depended on their EO concentration
(the higher the better), EO type (oregano EO the most active) and on the microbiological
group analysed (Pseudomonas spp. the most resistant). Films with 20 g kg1 of oregano EO showed their
efficacy by doubling the storage time of chicken breast (from 6 to 13 days), keeping most of the
microbiological groups below the recommended limits for distribution and consumption of chicken
breast. By comparing the effects of the direct addition of the EOs onto the chicken breast surfaces and the
results brought about by the development of edible coatings the usefulness and functionality of the latter
as carriers of antimicrobials has been confirmed.