Development of whey protein films inhibitory to spoilage and pathogenic bacteria.

摘要

Edible films and coatings are increasingly being developed as new types of packaging materials since plastic packaging materials are not easily biodegradable and create substantial amounts of solid waste. Antimicrobial edible films or coatings applied on food products have the potential to reduce the growth of spoilage and pathogenic bacteria, yeast and mold, thereby improving food quality and extending product shelf-life as well as reducing packaging waste.; Edible antimicrobial films were produced by incorporating nisin, lysozyme, ethylenediaminetetraacetic acid (EDTA) or propyl paraben (PP) into neutral or acidic whey protein isolate (WPI) films. The antimicrobial films were evaluated in agar for their ability to inhibit several spoilage and pathogenic organisms (Brochothrix thermosphacta, Listeria monocytogenes, Staphylococcus aureus, Salmonella Typhimurium and Escherichia coli 0157:147) that are significant contributors to food spoilage and outbreaks of foodborne illness. To determine film antimicrobial activity, 1 cm diameter discs of films were placed on bacteria-inoculated agar plates and/or tubes and the clear inhibition zones were measured in the horizontal and vertical directions. The antimicrobial activity was further quantified by enumerating bacterial numbers on the agar areas showing inhibition zones. (Abstract shortened by UMI.)