CUHK researchers develop biocellulose packaging
Scientists at The Chinese University of Hong Konghave developed an edible, transparent and biodegradable material with considerable potential for application in food packaging.
Plastic food packaging contributes significantly to landfill waste, leading researchers to explore bio-derived alternatives. Scientists at The Chinese University of Hong Kong have now developed an edible, transparent, and biodegradable material with great potential for use in food packaging.
Traditional plastic packaging, which relies on petrochemicals and lacks biodegradability, has long been a major factor in environmental pollution. A team at CUHK has focused on bacterial cellulose, an organic compound derived from some types of bacteria. bacterial cellulose is increasingly viewed as a sustainable, readily available, and non-toxic alternative to plastics.
Professor To Ngai from CUHK’s Department of Chemistry and corresponding author of the study highlighted the impressive tensile strength and versatility of bacterial cellulose as the key to its potential.
While plant cellulose is found in cell walls, bacterial cellulose can be produced through microbial fermentation, thus avoiding tree or crop harvesting. “This production method does not contribute to deforestation or habitat loss, making BC a more sustainable and environmentally friendly material alternative to plant cellulose,” Ngai said.
The widespread adoption of bacterial cellulose has been hindered by its sensitivity to moisture (hygroscopicity), affecting its physical properties. In a recent paper published in the SCI Journal of the Science of Food and Agriculture, CUHK researchers presented a novel approach to overcoming this limitation. By incorporating certain soy proteins and coating the material with an oil-resistant composite, the team successfully created an edible, transparent, and durable BC-based composite packaging.
Ngai believes this method is highly scalable, as it does not require specific reaction conditions like chemical reactions, but rather simple mixing and coating techniques.
The research showed that the plastic alternative can fully degrade within one to two months. Unlike some bio-derived plastics, such as polylactic acid, the BC-based composite does not require industrial composting conditions to degrade.
“The material developed in this research is completely edible, making it safe for turtles and other sea animals to consume without causing aquatic toxicity in the ocean,” Ngai explained.
CUHK researchers are now looking at ways to enhance the versatility of modified bacterial cellulose films for broader applications. They are developing a thermosetting glue to create strong bonds between bacterial cellulose, enabling it to be easily molded into various shapes when heated.
“One of the main challenges with bacterial cellulose films is that they are not thermoplastic, which limits their potential for use in certain applications. By addressing this issue, we hope to make bacterial cellulose films more competitive with traditional plastics while maintaining their eco-friendliness,” Ngai said.
The study aims to help reduce the excessive use of single-use plastics, which can persist for centuries after only a few days on supermarket shelves.
“This research serves as a reminder that natural raw materials may already possess the necessary characteristics to perform beyond the functions of plastic packaging,” Ngai concluded.
To see the Journal of the Science of Food and Agriculture paper click here.