New strategies to fabricate starch/chitosan-based composites by extrusion

Latest Trends in Sustainable Polymeric Food Packaging Films

Food packaging is the best way to protect food while it moves along the entire supply chain to the consumer. However, conventional food packaging poses some problems related to food wastage and excessive plastic production. Considering this, the aim of this work was to examine recent findings related to bio-based alternative food packaging films by means of conventional methodologies and additive manufacturing technologies, such as 3D printing (3D-P), with potential to replace conventional petroleum-based food packaging. Based on the findings, progress in the development of bio-based packaging films, biopolymer-based feedstocks for 3D-P, and innovative food packaging materials produced by this technology was identified. However, the lack of studies suggests that 3D-P has not been well-explored in this field. Nonetheless, it is probable that in the future this technology will be more widely employed in the food packaging field, which could lead to a reduction in plastic production as well as safer food consumption.

Efficient Photocatalytic Dye Degradation and Bacterial Inactivation by Graphitic Carbon Nitride and Starch-Doped Magnesium Hydroxide Nanostructures

The removal of hazardous pollutants from water is becoming an increasingly interesting topic of research considering their impact on the environment and the ecosystem. This work was carried out to synthesize graphitic carbon nitride (g-C₃N₄) and starch-doped magnesium hydroxide (g-C₃N₄/St-Mg(OH)₂) nanostructures via a facile co-precipitation process. The focus of this study is to treat polluted water and bactericidal behavior with a ternary system (doping-dependent Mg(OH)₂). Different concentrations (2 and 4 wt %) of g-C₃N₄ were doped in a fixed amount of starch and Mg(OH)₂ to degrade methylene blue dye from an aqueous solution with bactericidal potential against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) pathogens. The textural structures, morphological evolutions, and optical characteristics of the as-prepared samples were analyzed using advanced characterization techniques. X-ray diffraction confirmed the hexagonal phase of Mg(OH)₂ with improved crystallinity upon doping. Fourier transform infrared spectroscopy revealed Mg(OH)₂ stretching vibrations and other functional groups. UV-visible spectroscopy exhibited a red shift (bathochromic effect) in absorption spectra representing the decrease in energy band gap (E _g). Photoluminescence patterns were recorded to study recombination of charge carriers (e^- and h⁺). A significant enhancement in photodegradation efficiency (97.62%) and efficient bactericidal actions against E. coli (14.10 mm inhibition zone) and S. aureus (7.45 mm inhibition zone) were observed for higher doped specimen 4% g-C₃N₄/St-Mg(OH)_2.

Emerging chitosan-essential oil films and coatings for food preservation - A review of advances and applications

With the rising demand for fresh and ready-to-eat foods, antimicrobial packaging has been developed to control or prevent microbial growth as well as maintain food quality and safety. Chitosan is an advanced biomaterial for antimicrobial packaging to meet the growing needs of safe and biodegradable packaging. The application of natural essential oils as antimicrobial agents effectively controls the growth of spoilage and pathogenic microbes. Thus, chitosan edible coatings and films incorporated with essential oils have expanded the general applications of antimicrobial packaging in food products. This review summarized the effect of essential oils on modifying the physicochemical characteristics of chitosan-based films. Notably, the antimicrobial efficacy of the developed composite films or coatings was highlighted. The advances in the preparation methods and application of chitosan films were also discussed. Broadly, this review will promote the potential applications of chitosan-essential oils composite films or coatings in antimicrobial packaging for food preservation.