ARS | Publication request: Physical and antibacterial properties of edible films formulated with apple skin polyphenolics

Submitted to: Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: February 18, 2010
Publication Date: N/A

Technical Abstract: : Fruit and vegetables skins have polyphenolic compounds, terpenes, phenols and plant essential oil extracts with antimicrobial and antioxidant activity. These components are GRAS. Edible films made from fruits or vegetables containing apple skin polyphenolics have the potential to be used commercially to protect food against contamination by pathogenic bacteria. The main objective of this study was to evaluate physical properties as well as antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes of apple skin polyphenolics in apple puree film forming solutions (APFFS) formulated into edible films at 0-10% (w/w) concentrations. Antimicrobial activities of edible film containing apple skin polyphenolics were determined by overlay method. Commercial apple skin polyphenolics powder had a water activity of 0.44 and high total soluble phenolic compounds and antioxidant capacity (995.3 mg chlorogenic acid/100 g and 14.4 mg Trolox/g, respectively). Apple edible film with apple skin polyphenolics was highly effective against Listeria monocytogenes. The minimum concentration need to inactive Listeria monocytogenes was 1.5%. However, apple skin polyphenolic did not show any antimicrobial effect against E. coli O157:H7 and Salmonella enterica even at 10% level. The presence of apple skin polyphenolics reduced water vapor permeability of films. Apple skin polyphenolics increased elongation of films and darkened the color of films. The results of the present study show that apple skin polyphenolics can be used to prepare apple-based antimicrobial edible films with good physical properties for food applications by direct contact.