| Popis: |
The interest in producing renewable polymers from natural resources is considerably increased as the need for the reduction of the amount of plastic waste in the environment becomes urgent. Biopolymers are considered as an alternative raw material for the development of biodegradable packaging to plastic produced from petroleum. Starch, a renewable biopolymer consisting of amylose and amylopectin, is the most commonly used agricultural raw material for edible film manufacturing because it has low cost, easy to handle and totally biodegradable. In order to maintain the quality of foods, it is necessary to select the correct materials and appropriate technologies for the production of the packaging. Current trends include the development of packaging that interacts with food, called active biofilms or active packaging. Nanocomposites with antimicrobial function are highly useful for the minimization of the growth of contaminant microorganisms during the processing or storage of food and thereby the extension of shelf-life and improvement of food safety. Thus, this work aims to review the literature to identify the main components used in packaging with nanoparticles and the results in food preservation. For this purpose, a bibliographic survey of the last 5 years was carried out in the databases of Scielo, Science direct, Google academic and Periodicals CAPES, with the following indexers: nanocomposites, nanotechnology, active packaging, and antimicrobial packaging. Some studies demonstrated that metal oxide nanocomposites in packaging provide enhances polymer barrier properties, making the material stronger, more flame resistant, with better thermal properties and having favorable surface wettability and hydrophobicity. Studies have shown that silver nanoparticles have antimicrobial activity against Gram-negative and Gram-positive bacteria and fungi. Also, chitosan nanostructures, a natural composite, have wide antimicrobial effects. Some studies have focused on antimicrobial effects of nanostructures combining chitosan and other antimicrobial agents as carvacrol, oregano and thyme essential oil. It was observed that chitosan nanocomposites combined with layered silicate were significantly more effective against Staphylococcus aureus and Escherichia coli than both pure. Packaging that increases the shelf-life of perishable food while reducing food waste is a sustainable opportunity for innovative technology. |
