Researchers at Flinders University have developed a thin, flexible film using milk protein, starch, and nanoclay that fully breaks down in soil within 13 weeks. The material aims to serve as an eco-friendly alternative to single-use plastics for food packaging. The study, published in Polymers, highlights its potential to reduce plastic pollution.
Concerns over plastic waste have prompted scientists at Flinders University in South Australia to innovate with biodegradable materials. In a study published in the journal Polymers, researchers blended calcium caseinate—a form of the milk protein casein—with modified starch, bentonite nanoclay, glycerol, and polyvinyl alcohol. This combination produced a durable, flexible film mimicking conventional plastics while being environmentally degradable.
Soil tests demonstrated that the film decomposes steadily under normal conditions, achieving full breakdown in approximately 13 weeks. Microbial assessments confirmed low toxicity, with bacterial levels within acceptable limits for non-antimicrobial films. Professor Youhong Tang, a nanomaterials researcher at Flinders Institute for NanoScale Science and Technology, noted, "We would recommend further antibacterial evaluations in further testing and development." He emphasized the urgency of such innovations, stating that developing sustainable alternatives for food packaging is essential to slowing global pollution.
The project involved collaboration with chemical engineering experts from Universidad de Bogotá Jorge Tadeo Lozano in Colombia, including Nikolay Estiven Gomez Mesa and Professor Alis Yovana Pataquiva-Mateus. Gomez explained, "We were experimenting with caseinates to make milk-based nanofibers and found that it could be used to cast polymers similar to common packaging materials." He added that the formulation uses inexpensive, biodegradable ingredients to enhance strength and barrier performance.
Pataquiva-Mateus highlighted the broader implications: "Everyone can play a part in reducing their plastic use, and finding biodegradable polymer alternatives is an important part of science helping to find solutions for industry, consumers, and the environment. Most of our single use plastic comes from food packaging, so these sorts of options should be explored further and join the circular economy revolution to conserve resources."
Global plastic production has surged from 2 million tonnes in 1950 to 475 million tonnes in 2022, with about 60% used once and only 10% recycled. The Organisation for Economic Co-operation and Development warns that without action, production could rise 70% by 2040, exceeding 700 million tonnes annually.
