| dc.description.abstract | Abstract
The shift in consumer preferences towards nutritious foods with extended shelf life has prompted the adoption of innovative approaches in food packaging methods, notably the integration of smart packaging. This technology integrates principles from food science, analytical chemistry, polymer science, electronics, and biomedical engineering. Smart materials, integral to this technology, are characterized by their ability to monitor the ambient conditions surrounding the food and relay appropriate information to consumers regarding both the food product and its environmental settings, including factors like temperature and pH levels. Unlike active packaging strategies, smart packaging does not involve the release of compounds into the food; instead, it relies on interactive indicators, often comprising color-based compounds, to evaluate the chemical and microbial integrity of food items. This interactive feature facilitates assessments of variables such as temperature fluctuations during storage, regulation of oxygen levels, and monitoring the activity of foodborne microorganisms.
Objective: The objective of this research is to explore the efficacy of chitosan/soy protein isolate packaging incorporating green nanoparticles and anthocyanins sourced from pistachio shell exopericarp in prolonging the shelf life of rainbow trout.
Material and methods: The experimental procedures began with the creation of a biopolymer blend comprising chitosan/soy protein isolate infused with green nanoparticles through a single-step hydrothermal synthesis, alongside the extraction of anthocyanins sourced from pistachio shells. Glycerol was later integrated into the solution to serve as a stabilizing agent in the film fabrication process. Subsequently, the manufactured films underwent testing through mechanical assessments, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Lastly, the impact of these films on extending the shelf life of rainbow trout was evaluated.
Results: The outcomes of the research indicated the development of a uniform film with enhanced physical and mechanical attributes. These biopolymer films possessed a range of desirable qualities, including full protection against UV radiation, potent antibacterial effects against Listeria, Staphylococcus, Vibrio, and Pseudomonas strains with inhibitory zones measuring approximately 21.42, 18.64, 16.73, and 15.62 mm, respectively, along with robust antioxidant properties. Additionally, the films exhibited discernible color changes in reaction to pH buffers (ranging from 2 to 12) and volatile ammonia. In experimental testing involving CS/SPI/PHPA/PHP/-CD film packaging under two specific scenarios—a "smart test" monitoring fish freshness and an "active test" at 4°C—it was observed that the film changed color from light pink (indicative of fresh fish) to yellow/brown (indicative of spoiled fish) in scenario one, while in scenario two, it demonstrated the potential to extend the fish's shelf life by up to 12 days. The study illustrated the remarkable compatibility of these polymer films, positioning them as a highly promising option for swift and efficient on-site food quality assessment. Furthermore, their demonstrated ability to prolong the shelf life of fish and mitigate quality degradation during storage positions them as a standout candidate for versatile film applications within the food sector.
Conclusion: In summary, the development of multi-functional active and smart indicator films utilizing CD and anthocyanins sourced from pistachio hulls was successfully achieved. The integration of these compounds exhibited strong compatibility with CS/SPI-based films, leading to enhancements in the physical, mechanical, and microstructural characteristics of the films. The resulting CS/SPI/PHPA/PHP/-CD film demonstrated exceptional properties such as antioxidant, antibacterial, and UV-blocking capabilities, rendering it an excellent choice for packaging material. The film's visual color response to pH buffers and volatile ammonia was shown to be highly sensitive, presenting a gradual color shift from light pink to yellowish brown, easily discernible to the naked eye. This color transition remained consistent throughout the storage of fish samples, alongside parameters like PTC, PV, TVC, TBA, and TVB-N. Ultimately, the CS/SPI/PHPA/PHP/-CD films, acting as both smart and active materials, hold promise in extending the shelf life of food products and empowering consumers to visually assess the quality of stored food at refrigerated and ambient temperatures. The potential applications of these films in the food packaging industry offer significant prospects for improving food safety, enhancing quality, and reducing food wastage.
Keywords: Smart and active packaging, chitosan, pistachio shell extract, green nanoparticles, carbon dots | en_US |
