Submitted to: Food Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/26/2023
Publication Date: 1/29/2023
Citation: Jin, Z.T., Yadav, M.P., Qi, P.X. 2023. Antimicrobial and physiochemical properties of films and coatings prepared from bio-fiber gum and whey protein isolate conjugates. Food Control. 148:109666. https://doi.org/10.1016/j.foodcont.2023.109666.
Interpretive Summary: Antimicrobial films and coatings are able to protect foods from microbial contaminates and reduce or inhibit the growth of spoilage microorganisms and foodborne pathogens in packaged foods. This study developed a new type of antimicrobial packaging material using two bio-polymer conjugates and one essential oil. These films and coatings made from conjugate-oli combinations effectively reduced the populations of E. coli, Salmonella, Listeria, spoilage fungi and bacteria in growth media, tomatoes and fresh-cut apples. These films and coatings can be used for improving food safety and extending the shelf life of various foods.
Technical Abstract: Bio-fiber gum (BFG) was conjugated with whey protein isolate (WPI) at the mass ratio of 3:1 WPI:BFG through a Maillard-type reaction. BFG was also composited with chitosan (CHI), at mass ratio 3:1 BFG:CHI to yield BFG+CHI. Both WPI:BFG and BFG+CHI containing 1% carvacrol were used to develop antimicrobial food packaging films and coatings. The antimicrobial efficacies of the films against E. coli, Salmonella, Listeria, spoilage fungi, and bacteria were evaluated using both in vitro and in vivo tests. The physicochemical properties of composite films were evaluated to determine their potential for food packaging applications. Both films effectively reduced the populations of E. coli, Listeria and native microorganisms in tomatoes and fresh-cut apples stored at 4 ºC for 7 and 21 days, as well as populations of Salmonella and bread fungi in growth media. However, WPI:BFG conjugate films maintained their antifungal properties for a longer period of time and could be reused more than the BFG+CHI composite film. The results also revealed that WPI:BFG conjugate films had less water solubility, lower permeability to oxygen and carbon dioxide, and higher mechanical strength than BFG+CHI composite film. These films and coatings can be used for various foods by direct food surface coating and headspace releasing methods.