|ESPITIA, PAULA - Universidade Federal De Vicosa|
|Avena Bustillos, Roberto|
|Wood, Delilah - De|
|SOARES, NILDA - Universidade Federal De Vicosa|
Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/4/2014
Publication Date: 5/1/2014
Citation: Espitia, P.J., Avena Bustillos, R.D., Du, W., Williams, T.G., Wood, D.F., Chiou, B., Mchugh, T.H., Soares, N.F. 2014. Physical and antibacterial properties of Açaí edible films formulated with thyme essential oil and apple skin polyphenols. Journal of Food Science. 79(5):903-910. doi: 10.1111/1750-3841.12432.
Interpretive Summary: The study of physical properties of edible films is essential for industrial application. However, few works have combined studies of antimicrobial activity with the effects of antimicrobials on packaging physical properties. This work showed the potential application on food preservation of açaí edible films due to their antibacterial activity and synergistic combination of both antimicrobials (apple skin polyphenols and thyme essential oil) as well as their good physical properties.
Technical Abstract: Açaí edible films incorporated with apple skin polyphenols (ASP), thyme essential oil (TEO) or their mixture were developed as antimicrobial active packaging for food preservation. Antimicrobial activity of açaí edible films against Listeria monocytogenes was evaluated. The effects of both antimicrobial compounds on physical-mechanical properties of açaí edible film, including mechanical properties, water vapor permeability, color, thermal stability and microstructure, were also assessed. Açaí edible films incorporated with TEO, ASP or their mixture showed antimicrobial activity against L. monocytogenes. Incorporation of both compounds in the films resulted in combined antimicrobial effect. Addition of ASP resulted in improved mechanical properties, whereas incorporation of TEO diminished film mechanical resistance. Incorporation of ASP or TEO had no significant effect on water vapor permeability of films. Açaí edible films containing ASP were lighter and had more red color than the control film. Incorporation of ASP resulted in improved film thermal stability, whereas addition of TEO caused rapid thermal decomposition. Presence of clusters was observed on the surface of açaí edible films. Addition of ASP resulted in a smother surface, whereas addition of TEO led to the formation of crater-like pits on the film surface. The results of this study indicated that açaí edible films formulated with ASP and TEO have the potential to be used for food preservation due to their combined antibacterial activity as well as their good physical-mechanical properties.