Antimicrobial efficiency of edible coatings on the preservation of chicken breast fillets

- Evaluation of the effectiveness of WPI coatings as carriers of natural preservatives.
- WPI coatings with 20 g kg−1 of oregano EO doubled the shelf-life of chicken breast.
- Efficacy depended on type and concentration of added EO and bacterial target.
- The WPI matrix remained fundamental for the success of the formulations.

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 kg−1 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.