Chitosan‐nanocomposites as a food active packaging: Effect of addition of tocopherol and modified montmorillonite

Development of chitosan-based films with invertase enzyme for active packaging: Physicochemical parameters, structure, application, and storage

The use of active packaging made from biodegradable polymers can contribute to the environment and to the food industry by increasing the shelf life of their products. This study aimed to produce chitosan-based films incorporated with the invertase enzyme (1, 2, 5, 9, and 10 %) as an alternative to avoid sucrose crystallization in the confectionery industry. The optimum activity of the invertase enzyme was observed at 55 °C and pH 5, thus, the films made with the film-forming solution adjusted to pH 5 and dried at 55 °C were compared with those without pH adjustment and dried at room temperature. Regarding the thermogravimetric analysis (TGA), the greatest weight of loss of the films was observed between 200 and 400 °C, which may be due to the volatilization of moisture from the polymeric films and the depolymerization and pyrolytic decomposition of chitosan. Adjusting the pH and temperature increased the surface roughness and cross-section of the films and increased the elongation at break, solubility (13.38 to 39.50 %), thickness (0.12 to 0.27 mm), and water vapor permeability ratio (2.95 to 8.47 10-10 g/(m × s × Pa)), in addition to reducing the stiffness and tensile strength. The color parameters were little affected by this change and the insertion of invertase, which acted as a plasticizer, reducing the tensile properties and increasing the flexibility, keeping the water vapor permeability ratio constant. The invertase-based films prevented crystal formation, and the candies exhibited similar or superior physicochemical characteristics compared to those packaged in cellophane. However, a temperature of 35 °C increased water loss. The films demonstrated enzymatic activity and good properties, especially those with pH and temperature adjustments, and may serve as a promising alternative to cellophane for candy packaging in the sugary food industry.

Development of controlled-release antioxidant poly (lactic acid) bilayer active film with different distributions of α-tocopherol and its application in corn oil preservation

The antioxidant poly (lactic acid) bilayer active films with a different distribution of α-tocopherol (TOC) in two layers (outer layer/inner layer: 0%/6%, 2%/4%, 3%/3%, 4%/2%, 6%/0%) were developed. The effects of TOC distribution on the structural, physicochemical, mechanical, antioxidant and release properties of the films and their application in corn oil packaging were investigated. The different distributions of TOC showed insignificant effects on the color, transparency, tensile strength and oxygen and water vapor barrier properties of the films, but it affected the release behavior of TOC from the films into 95% ethanol and the oxidation degree of corn oil. The film with higher TOC in outer layer showed a slower release rate. The corn oil packaged by the film containing 4% TOC in outer layer and 2% TOC in inner layer exhibited the best oxidative stability. This concept showed a great potential to develop controlled-release active films for food packaging.

Current Applications of Bionanocomposites in Food Processing and Packaging

Nanotechnology advances are rapidly spreading through the food science field; however, their major application has been focused on the development of novel packaging materials reinforced with nanoparticles. Bionanocomposites are formed with a bio-based polymeric material incorporated with components at a nanoscale size. These bionanocomposites can also be applied to preparing an encapsulation system aimed at the controlled release of active compounds, which is more related to the development of novel ingredients in the food science and technology field. The fast development of this knowledge is driven by consumer demand for more natural and environmentally friendly products, which explains the preference for biodegradable materials and additives obtained from natural sources. In this review, the latest developments of bionanocomposites for food processing (encapsulation technology) and food packaging applications are gathered.

Chitosan Based Biodegradable Composite for Antibacterial Food Packaging Application

A recent focus on the development of biobased polymer packaging films has come about in response to the environmental hazards caused by petroleum-based, nonbiodegradable packaging materials. Among biopolymers, chitosan is one of the most popular due to its biocompatibility, biodegradability, antibacterial properties, and ease of use. Due to its ability to inhibit gram-negative and gram-positive bacteria, yeast, and foodborne filamentous fungi, chitosan is a suitable biopolymer for developing food packaging. However, more than the chitosan is required for active packaging. In this review, we summarize chitosan composites which show active packaging and improves food storage condition and extends its shelf life. Active compounds such as essential oils and phenolic compounds with chitosan are reviewed. Moreover, composites with polysaccharides and various nanoparticles are also summarized. This review provides valuable information for selecting a composite that enhances shelf life and other functional qualities when embedding chitosan. Furthermore, this report will provide directions for the development of novel biodegradable food packaging materials.