Nanotechnology doubles shelf life of milk when used in PE packaging

A Brazilian agribusiness company says it has doubled the shelf life of fresh milk by incorporating silver-based microparticles into the plastic packaging.

Agrindus, located in São Carlos, says that the bacterial, antimicrobial and self-sterilising properties of the particles increase the shelf life of the milk from seven to 15 days when stored in the rigid plastic bottles. The technology was developed by Nanox, a fellow Brazilian company specialising in nanotechnology.

"We already knew use of our antimicrobial and bactericidal material in rigid or flexible plastic food packaging improves conservation and extends shelf life. So we decided to test it in the polyethylene used to bottle grade A fresh milk [whole milk] in Brazil. The result was that we more than doubled the product's shelf life solely by adding the material to the packaging, without mixing any additives with the milk,” said Luiz Pagotto Simões, CEO of Nanox.

According to Simões, the microparticles are included as a powder in the polyethylene preform that is used to make plastic bottles by blow or injection moulding. The microparticles are inert, so there is no risk of them detaching from the packaging and coming into contact with the milk.

Tests of the material's effectiveness in extending the shelf life of fresh milk were performed over the course of a year by Agrindus, Nanox and independent laboratories. "Only after shelf life extension had been certified did we decide to bring the material to market," Simões said.

"In milk bags, the material is capable of extending shelf life from four to ten days," he said.

Nanox plans to market the product in Europe and the United States, where much larger volumes of fresh milk are consumed than in Brazil.