Recently, interest in smart packaging, which can show the color change of the packaging film according to the state of the food and evaluate the quality or freshness of the packaged food in real-time, is increasing. As a color indicator, a natural colorant, anthocyanin, drew a lot of attention due to their various colors as well as useful functions properties such as antioxidant activity and anti-carcinogenic and anti-inflammatory effects, prevention of cardiovascular disease, obesity, and diabetes. In particular, the pH-responsive color-changing function of anthocyanins is useful for making color indicator smart packaging films. This review addressed the latest information on the use of natural pigment anthocyanins for intelligent and active food packaging applications. Recent studies on eco-friendly biodegradable polymer-based color indicator films incorporated with anthocyanins have been addressed. Also, studies on the use of smart packaging films to monitor the freshness of foods such as milk, meat, and fish were reviewed. This review highlights the potential and challenges for the use of anthocyanins as pH-responsive color-changing films for intelligent food packaging applications, which may be beneficial for further development of smart color indicator films for practical use.

Anthocyanin food colorant and its application in pH-responsive color change indicator films.

Gelatin/carrageenan-based functional intelligent film was fabricated by incorporating shikonin and propolis. The shikonin solution extracted from the gromwell (Lithospermum erythrorhizon) root show...

Preparation of Gelatin/Carrageenan-Based Color-Indicator Film Integrated with Shikonin and Propolis for Smart Food Packaging Applications

PVOH-based multifunctional films were fabricated by blending with grapefruit seed extract (GSE) and curcumin using a solvent casting technique. Both fillers (GSE and curcumin) were mixed well and evenly spread in the polymer matrix to form a compatible composite with PVOH. The addition of GSE and curcumin improved the UV-barrier (>95 %) and mechanical properties (30 %) of the PVOH film. Besides, functional properties like antioxidant and antibacterial actions were increased meaningfully by incorporating GSE and curcumin. However, the incorporation of GSE and curcumin slightly reduced the water vapor barrier property of the film without changing the thermal stability. When the combination of GSE and curcumin was used in a composite film, a unique effect was seen on the film properties. The PVOH/GSE/curcumin film with enhanced mechanical and functional properties can be used for active food packaging applications.

Antioxidant and antimicrobial poly(vinyl alcohol)-based films incorporated with grapefruit seed extract and curcumin

Gelatin/agar-based functional film integrated with Pickering emulsion of clove essential oil stabilized with nanocellulose for active packaging applications

Fabrication of cellulose nanofiber-based functional color indicator film incorporated with shikonin extracted from Lithospermum erythrorhizon root

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.

Leonardo Peres Vieira

Papers

Potentials Nanocomposites in Food Packaging