Researchers at The Chinese University of Hong Kong (CUHK) have made a significant breakthrough in the development of sustainable food packaging materials. In a study published in the Journal of the Science of Food and Agriculture, the scientists have created an edible, transparent, and biodegradable material that shows great promise for use in food packaging.
Plastic food packaging is a major contributor to the global plastic waste problem, with a large portion ending up in landfills. To address this environmental concern, the CUHK team turned to bacterial cellulose (BC), an organic compound derived from certain types of bacteria. BC is known for its strength and versatility and has gained attention as a sustainable and non-toxic alternative to traditional plastics.
Unlike cellulose derived from plants, BC can be produced through microbial fermentation, eliminating the need for deforestation or crop harvesting. This makes BC a more environmentally friendly option for packaging materials. However, BC has been limited in its use due to its sensitivity to moisture in the air, which affects its physical properties.
The researchers overcame this limitation by incorporating specific soy proteins into the BC structure and coating it with an oil-resistant composite. This innovative approach resulted in the creation of an edible, transparent, and durable BC-based composite packaging material.
The development of this bio-derived packaging material represents a significant step forward in addressing the environmental impact of plastic food packaging. By utilizing BC, which is both sustainable and biodegradable, researchers are paving the way for more eco-friendly alternatives that can help reduce plastic waste and its detrimental effects on the environment.
The researchers at CUHK also highlighted the scalability of their approach, emphasizing that it offers a simple and practical method for large-scale production. Unlike chemical reactions, this method does not require specific reaction conditions but rather involves mixing and coating, making it highly feasible for implementation on a larger scale.
The study demonstrated that the BC-based composite material could be fully degraded within a short period of 1-2 months. What sets it apart from other bio-derived plastics like polylactic acid is that it doesn’t require specific industrial composting conditions for degradation.
An important aspect of this innovative material is its edibility, ensuring that it poses no harm to marine life. Ngai emphasized that sea animals, including turtles, can safely consume this material without causing any aquatic toxicity in the ocean.
Moving forward, the researchers at CUHK are focused on further enhancing the versatility of modified BC films, expanding their potential applications. They are particularly interested in developing a thermosetting glue that would allow bacterial cellulose to be easily molded into various shapes when heated. By addressing the issue of BC films not being thermoplastic, they aim to make them more competitive with traditional plastics while maintaining their eco-friendliness.
Ngai expressed his hope that this research will contribute to reducing the excessive use of single-use plastics, which can persist in the environment for hundreds of years despite their short shelf life. The study serves as a reminder that natural raw materials may already possess the necessary characteristics to outperform plastic packaging, showcasing the potential of sustainable alternatives.
Source: Society of Chemical Industry