Effect of plasticizing and crosslinking at room temperature on microstructure replication using soft lithography on zein films

Recent advances in the production of bionanomaterials for development of sustainable food packaging: A comprehensive review

Polymers originating from natural macromolecule based polymeric materials have gained popularity due to the demand for green resources to develop unique, eco-friendly, and high-quality biopolymers. The objective of this review is to address the utilization of bionanomaterials to improve food quality, safety, security, and shelf life. Bionanomaterials are synthesized by integrating biological molecules with synthetic materials at the nanoscale. Nanostructured materials derived from biopolymers such as cellulose, chitin, or collagen can be employed for the development of sustainable food packaging. Green materials are cost-effective, biocompatible, biodegradable, and renewable. The interaction of nanoparticles with biological macromolecules must be analyzed to determine the properties of the packaging film. The nanoparticles control the growth of bacteria that cause food spoiling by releasing distinctive chemicals. Bio-nanocomposites and nanoencapsulation systems have been used in antimicrobial bio-based packaging solutions to improve the efficiency of synergism. Nanomaterials can regulate gas and moisture permeability, screen UV radiation, and limit microbial contamination, keeping the freshness and flavor of the food. Food packaging based on nanoparticles embedded biopolymers can alleviate environmental concerns by lowering the amount of packaging materials required and enhancing packaging recyclability. This results in less waste and a more eco-sustainable approach to food packaging. The study on current advances in the production of bionanomaterials for development of sustainable food packaging involves a detailed investigation of the available data from existing literature, as well as the compilation and analysis of relevant research results using statistical approaches.

Improvement of Natural Polymeric Films Properties by Blend Formulation for Sustainable Active Food Packaging

Active packaging manufactured with biopolymers extracted from agri-food waste is one of the most innovative and eco-sustainable strategies for maintaining food quality. However, biopolymers often present poor performances, which hinders their competitiveness compared with plastics. This work focused on developing and optimizing a natural polymeric blend produced by solvent casting based on zein and chitosan to improve the pure biopolymers' properties. The best results were obtained by blending zein and chitosan in a 1:2 weight ratio. The films were characterized in terms of morphology, mechanical and oxygen barrier properties, thermal stability, transparency and wettability. The blend production allowed us to obtain lower brittleness and lower stiffness materials compared with pure polymer films, with oxygen permeability values two orders of magnitude lower than pure zein, better optical properties with respect to pure chitosan and good thermal stability. The wettability properties of the blend did not result in being altered with respect to the single polymer, which was found to have hydrophilic behavior, highlighting the strong influence of glycerol used as a plasticizer. The results suggested that the polymer blending strategy is a viable and cost-effective method for producing packaging materials as alternatives to plastics.

Production and characterization of biodegradable bi-layer films from poly(lactic) acid and zein

Recently, packaging industry has turned to biodegradable packaging, and poly(lactic acid) has become the most remarkable polymer. However, the high oxygen permeability of PLA films significantly limits their use. Therefore, this study, it was aimed to improve the oxygen barrier properties of PLA films without adversely affecting the mechanical and water vapor barrier properties. Biodegradable PLA-Zein bi-layer films were produced by changing PLA and zein thickness. Transparent and UV barrier bi-layer films were obtained. Mechanical properties of PLA films were improved by the production of bi-layer films. Water vapor permeability of bi-layer films increased whereas the permeance decreased with zein coating of PLA. Multi-criteria decision hierarchy was used to select the best bi-layer films based on mechanical, permeance, and opacity results. Oxygen barrier properties of PLA film significantly improved by zein coating, and hydrophobicity of PLA film was not affected by zein coating. The crystallization and melting temperatures of films decreased when compared to PLA films, supporting the mechanical results. Homogeneous, non-porous, and smooth film surface was obtained and zein layer was in good compatibility with PLA layer. These results suggest that zein coatings could be used to decrease oxygen permeability of PLA films without negatively affecting other properties.

Novel Nondestructive Biosensors for the Food Industry

An increasing number of foodborne outbreaks, growing consumer desire for healthier products, and surging numbers of food allergy cases necessitate strict handling and screening of foods at every step of the food supply chain. Current standard procedures for detecting food toxins, contaminants, allergens, and pathogens require costly analytical devices, skilled technicians, and long sample preparation times. These challenges can be overcome with the use of biosensors because they provide accurate, rapid, selective, qualitative, and quantitative detection of analytes. Their ease of use, low-cost production, portability, and nondestructive measurement techniques also enable on-site detection of analytes. For this reason, biosensors find many applications in food safety and quality assessments. The detection mechanisms of biosensors can be varied with the use of different transducers, such as optical, electrochemical, or mechanical. These options provide a more appropriate selection of the biosensors for the intended use. In this review, recent studies focusing on the fabrication of biosensors for food safety or food quality purposes are summarized. To differentiate the detection mechanisms, the review is divided into sections based on the transducer type used.