Enhanced mechanical and water resistance properties of gelatin-based antimicrobial films via a double crosslinked network.

For a sustainable future, the search for biodegradable materials to replace conventional petroleum‐based polymers for food packaging has received much attention because of the need to reduce plastic pollution in the environment. Biopolymers are generally biodegradable, renewable, nontoxic, and easily available in nature and can be effective potential alternatives to synthetic plastics. However, the inherent limitations of biopolymers in terms of poor mechanical and barrier properties, as well as inadequate thermal stability, have hindered their widespread adoption in the food packaging industry. With the advent of nanoscience, new avenues for innovation in novel food packaging materials with enhanced functional attributes have been realized. Upon dispersion in a biopolymer matrix, inorganic or organic nanofillers, which possess certain physical and chemical properties at the nanoscale, make these composites useful as packaging materials; tailored mechanical, barrier, thermal, and optical properties have been reported to meet specific requirements for food preservation and packaging. This review discusses the effects of the reinforcement of different types of nanofillers on the mechanical, barrier, antimicrobial and antioxidant properties of biopolymeric matrices used for food packaging applications. The importance of standardized regulations for the safe use of nanomaterials in food packaging has also been discussed in detail.

This study addresses the gap in research on the application of thermochromic polymers (TPs) in food packaging and their potential for real-time temperature monitoring, aiding in the assessment of food quality and shelf-life. TPs exhibit a visible color change in response to temperature variations. A comprehensive systematic review (SR) across multiple engineering peer-review databases using predefined terms was conducted. Additionally, international patent databases were investigated using the same predefined terms. Independent experts reviewed the methodology to identify and address potential biases. A total of 288 eligible articles and 922 patents were identified. After a duplicate selection and extraction process according to the inclusion criteria, four related full-text publications were selected from the initial 288 articles, and five relevant patents were selected from the 922 patents. The qualitative review suggests that TPs hold significant promise as food packaging materials due to their unique physical properties. The study concludes that TPs offer valuable properties for the food packaging industry, meriting further investigation to exploit their benefits fully.

Chapter 6 focuses on the applications of polymers in food packaging and protection that include polymeric traditional packaging, polymeric coatings in metal-can food packaging, polymeric biodegradable and preservative food packaging, polymeric active packaging, and modified atmospheric and smart food packaging. Traditionally, food packages are used to provide protection for the food products and designed to retard or delay the undesirable effects of the physical, chemical, biological, and environmental factors that extend shelf life and food quality by keeping the food contents clean, fresh, and safe to aid consumers in using the nutritional contents of the food products. Their primary role in food safety is preservation and protection from external contamination, maintenance of food quality, and increase shelf life. They protect foods from the influences of environment effects such as light, heat, oxygen, moisture, enzymes, microorganisms, insects, dust, gaseous emission, and pressure, which lead to the deterioration of food products. Food packages are labeled to show required information on the nutrition of the food content and to communicate the consumer how to use, transport, recycle, or dispose the package, as well as the nature of the deterioration of the product and any subsequent health problems if food is consumed beyond expiry date due to the potential serious nature of consumption of pathogens

Packaging plays a crucial role in protecting food by providing excellent mechanical properties as well as effectively blocking water vapor, oxygen, oil, and other contaminants. The low degradation of widely used petroleum-based plastics leads to environmental pollution and poses health risks. This has drawn interest in renewable biopolymers as sustainable alternatives. The seafood industry generates significant waste that is rich in bioactive substances like chitin, chitosan, gelatins, and alginate, which can replace synthetic polymers in food packaging. Although biopolymers offer biodegradability, biocompatibility, and non-toxicity, their films often lack mechanical and barrier properties compared with synthetic polymer films. This comprehensive review discusses the chemical structure, characteristics, and extraction methods of biopolymers derived from seafood waste and their usage in the packaging area as reinforcement or base materials to guide researchers toward successful plastics replacement and commercialization. Our review highlights recent advancements in improving the thermal durability, mechanical strength, and barrier properties of seafood waste-derived packaging, explores the mechanisms behind these improvements, and briefly mentions the antimicrobial activities and mechanisms gained from these biopolymers. In addition, the remaining challenges and future directions for using seafood waste-derived biopolymers for packaging are discussed. This review aims to guide ongoing efforts to develop seafood waste-derived biopolymer films that can ultimately replace traditional plastic packaging.

Stepwise reinforcement strategy for guar gum/sodium alginate based films: Introduction of carboxylated cellulose nanofibers by different methods and further calcium ion crosslinking

Nano and nanocomposite antimicrobial materials for food packaging applications

Plastic application is one of the crucial concerns due to the global environmental impact, and shifting to biodegradable food packaging would be a favorable option. This review aims to use biodegradable microbial-derived polymers in food packaging. The main criteria in food application are mechanical and thermal characteristics and water vapor gas transfer. Among materials, microbial polymers, polysaccharides, and polyhydroxyalkanoate are desirable in food packaging due to being biodegradable, having better physical properties, and lower O2 and CO2 permeability with no catalysts residue. This article focuses on microbial polysaccharides (e.g., bacterial cellulose) and polyhydroxyalkanoate in food packaging. The necessity of using biobased polymers in food packages is expressed in the introduction part. The application of the most common biopolymers is described. The biopolymers production, polyhydroxybutyrate-based nanocomposites, and some microbial polysaccharide (e.g., BC) properties in food packaging are also discussed. Moreover, some improvement issues of polyhydroxybutyrate and microbial polysaccharide (e.g., BC) properties are explained, and the nanotechnology impresses on improving the physical properties. Eventually, the article includes some possible future trends.KeywordsPoly(hydroxybutyrate)Poly(hydroxyalkanoate)Food packagingPropertiesModificationsNanoparticlesMicrobial polisaccharides and bacterial celulose

Mechanical and water barrier properties of isolated soy protein composite edible films as affected by carvacrol and cinnamaldehyde micro and nanoemulsions

Hemicellulose has potential advantages in food packaging because of its abundant reserves, degradability and regeneration. However, compared with fossil-derived plastic films, hemicellulose-based films show inferior hydrophobicity and barrier properties because of their low degree of polymerization and strong hydrophilicity. Focusing on such issues, this work covers the modification of a xylan/polyvinyl alcohol (PVOH) film using 1,2,3,4-butane tetracarboxylic acid (BTCA) as esterifying agent. The thus prepared composite film was more compact owing to the esterification reaction with xylan and PVOH forming a crosslinked network structure and reducing the distance between molecular chains. The results showed that BTCA had a positive effect on the oxygen barrier, hydrophobicity and mechanical properties of the composite film. The tensile strength of the xylan/PVOH composite film with 10% BTCA content increased from 11.19 MPa to 13.99 MPa. A 20% BTCA loading resulted in an increase in the contact angle of the composite film from 87.1° to 108.2°, and a decrease in the oxygen permeability from 2.11 to 0.43 (cm3·µm)/(m2·d·kPa), corresponding to increase in the contact angle by 24% and a decrease in oxygen permeability by 80%. The overall performance enhancement indicates the potential application of such composites as food packaging.

Role of Green Polymers in Food Packaging

Recent advances in protein-polysaccharide based biocomposites and their potential applications in food packaging: A review

Chapter 5 - Biobased polymers in packaging

Bio-based composite films have been widely studied as potential substitutes for conventional plastics in food packaging. The aim of this study was to develop multifunctional composite films by introducing cellulose nanofibers (CNF) and lignin into starch-based films. Instead of costly and complicated chemical modification or covalent coupling, this study optimized the performance of the composite films by simply tuning the formulation. We found that starch films were mechanically reinforced by CNF, with lignin dispersing as nanoparticles embedded in the matrix. The newly built-up hydrogen bonding between these three components improves the integration of the films, while the introduction of CNF and lignin improved the thermal stability of the starch-based films. Lignin, as a functional additive, improved hydrophobicity and blocked UV transmission. The inherent barrier property of CNF and the dense starch matrix provided the composite films with good gas barrier properties. The prepared flexible films were optically transparent, and exhibited UV blocking ability, good oxygen-barrier properties, high hydrophobicity, appreciable mechanical strength and good thermal stability. These characteristics indicate potential utilization as a green alternative to synthetic plastics especially for food packaging applications.

A polylactic acid-polyethylene glycol block copolymer (PLA-b-PEG) was used as an additive to prepare gelatin/PLA-b-PEG blend films for the first time. The PEG molecule block enhanced the compatibility of the PLA molecule block with gelatin, which greatly improved the excellent mechanical and gas barrier properties of the gelatin film. The film contained 5 wt% PLA-b-PEG possessed the highest tensile strength and the highest elastic modulus. When the PLA-b-PEG content further increased to 20 wt%, the tensile strength, elastic modulus and elongation at the break of the blend film were all higher than pure gelatin film, suggesting that the gelatin/PLA-b-PEG blend film was pliable and tough. The blend film possessed not only excellent oxygen barrier property, but also a much-improved water barrier property. The degradation rate of the blend film was elongated controllably by regulating the content of the PLA-b-PEG copolymer. The blend film showed great potential in the application of food packaging.

Functional enhancement of biopolymer was attempted in this work for food packaging application. Incorporation of chitosan (0–9%) and silica (0–10%) nanoparticles (NP's) into gelatin film (Gel) has been tried and their effects on moisture content, tensile strength (TS), elongation at break (%E), wettability, water vapor permeability (WVP), and antimicrobial activities were studied. Morphology of nanoparticles was studied using scanning electron microscopy and transmission electron microscopy. Chitosan NP's showed agglomeration at higher concentration which leads to lower the mechanical as well as barrier properties of the film. However, silica NP's enhanced the properties of bionanocomposite film. TS was increased from 6.05 MPa of pure gelatin film to a maximum value of 38.91 MPa at CS NP's of 5.8% and Si NP's of 7%; however, %E decreased with addition of nanoparticles resulting in brittleness of film. WVP for pure gelatin film was 25.21 g mm/kPa m2 day, which reduced to 3.30 g mm/kPa m2 day after incorporation of 10% Si NP's. Antimicrobial activity was observed against E. coli and S. aureus. Incorporation of CS NP's improved the antimicrobial activity of gelatin film. Si NP's showed improvement in mechanical and barrier properties of Gel–CS films, however, had no effect on antimicrobial activities.Practical ApplicationResearchers community are more concerned of natural biopolymers to reduce the use of synthetic polymers, especially in food packaging. Gelatin is one of the natural biopolymer and have potential to be used as food packaging material. Problem with gelatin and many other biopolymer based film is their poor mechanical and barrier properties. Present study was framed to overcome these problems by incorporating silica and chitosan nanoparticles in gelatin film. The results observed would be useful to develop a biopolymer based nanocomposite film with improved mechanical, barrier and antimicrobial properties, which can be used for active food packaging.