Milk-based biodegradable films offer sustainable food packaging solution – scientists reveal

AUSTRALIA – Scientists have developed a biodegradable film for food packaging using calcium caseinate, a milk protein derivative, combined with modified starch and bentonite nanoclay. 

The material, created through a collaboration between Flinders University in Australia and Universidad de Bogotá Jorge Tadeo Lozano in Colombia, aims to replace traditional plastic packaging with a sustainable alternative. 

The film, enhanced with glycerol and polyvinyl alcohol for improved flexibility and durability, shows promise for reducing plastic pollution in the food industry.

Nikolay Estiven Gomez Mesa, a chemical engineering researcher, told Packaging Insights, “These films are made from renewable sources like starch and clay, fully biodegradable, and help combat long-term plastic pollution.” 

The research team, part of the Nanobioengineering Research Group, found that incorporating bentonite nanoclay enhances the film’s barrier properties, reducing water vapor permeability and protecting against UV light, which extends the shelf life of packaged goods. 

Gomez noted that the combination of biomaterials creates a polymer that balances strength and flexibility while minimizing brittleness.

The study revealed that the films completely degrade within 13 weeks under normal soil conditions, supporting circular economy initiatives by valorizing dairy waste streams, such as expired pasteurized skim milk, into sustainable packaging. 

A microbial analysis confirmed that bacterial levels remained within safe limits for non-antimicrobial biodegradable films, though further antibacterial testing was recommended.

Gomez explained that the hydrophilic nature of casein-starch films can be a challenge for high-moisture foods, but nanoclay creates tortuous pathways to slow water vapor transmission, improving durability.

For oily foods, additional coatings could further enhance resistance, depending on industry needs.

The researchers emphasized that all food-contact packaging must undergo rigorous migration and stability testing to meet international safety standards. 

Gomez stated, “Further evaluation against pathogens like E. coli and Listeria is critical for applications like cheese packaging to ensure safety and performance.”

Recent advancements in sustainable packaging complement this research.

A 2025 study published in Food and Bioprocess Technology highlighted starch-based films with bioactive compounds like carvacrol, showing improved tensile strength and antimicrobial properties for meat packaging. 

These developments indicate a growing trend toward biopolymer-based solutions to address environmental concerns. 

With global plastic consumption for packaging projected to nearly triple by 2060, costing an estimated US$1.2 trillion annually, such innovations offer affordable, eco-friendly alternatives for the food industry, paving the way for reduced waste and enhanced sustainability.

Subscribe to receive our email newsletters with the latest news and insights from Africa, the Middle East and around the world. SUBSCRIBE HERE