Spider web nano-machine could spin new packaging opportunities

Electrospinning, an emerging technology that forms a mat of fine fibres, could deliver new packaging materials, potentially produced from waste streams, for bakers and snacks makers.

With its roots in electrostatic spraying, electrospinning basically uses a high voltage electrical charge to draw very fine fibres, typically on a micro or nano scale, from polymer substances like proteins and cellulose.

Researchers at New Zealand's Crop & Food Research body, inspired by the intricate way a spider spins its web to produce tough, lightweight composite materials that have a greater tensile strength than steel of the same diameter, have been testing the potential of electrospun proteins and polysaccharides as industrial raw materials.

Master's graduate Jon Stanger, whose research into producing ultra-fine nano fibres is supported by Crop & Food Research, has gone on, in collaboration with partners, to develop a commercial electrospinning machine that "is being sold to research laboratories around the world."

On electrospinning, Stanger says: "I'm trying to take it to a level where we can design and produce industrial scale machines and find ways of increasing volumes of production."

"The serious work is underway that will develop real world applications and take it out of the blue skies area," he adds.

Electrospinning is firmly nestled in the nascent science of nanotechnology, a burgeoning technology for the food industry that leverages the science of the miniscule to develop new products and processes.

Nanotechnology is the ability to measure, see, manipulate and manufacture materials at usually between 1 and 100 nanometres. A nanometre is one billionth of a meter. A human hair is roughly 100,000 nanometers wide.

According to a study by consultant Helmut Kaiser, global sales of nanotechnology products to the food and beverage packaging sector jumped to US$860m (€687.5m) in 2004 from US$150m (€120m) in 2002.

The German firm predicts that nanotechnology will change 25 per cent of the food packaging business in the next decade leading to a yearly market of about $30bn (€24bn).

Crop & Food Research say the new firm established to commercialise the electrospinning machine, Electrospinz, was set up by Neil Buunk, technical director of Blenheim-based Potatopak, which makes food packing trays from potato processing waste.

One of the materials being trialled by Jon Stanger, Crop & Food Research and Electrospinz is marine collagen, normally part of the waste stream from hoki processing in New Zealand.

According to the New Zealand research firm, the country already exports "BSE-free collagens from cows", and claims there could be demand for "high value, electrospun material made from marine collagen."

While electrospinning has been around for many years, Nick Tucker, research leader in biomaterials for Crop & Food Research, says it was viewed as a technical curiosity until the 1980s when its potential for producing nano fibres was recognised.

The machine, five of which have already been sold to research teams in New Zealand, the UK and Germany, can spin fibre down to 100 nanometres in diameter, which is about ten thousandths of the thickness of a human hair and smaller than the wavelength of visible light, explains the research firm.

"The machine is easy to modify and we custom make them," adds Mr. Buunk.

Mr Buunk was visiting Crop & Food Research on other business "when he noticed Jon's prototype electrospinning machine and saw the possibilities in making small scale lab spinning machines," comments the New Zealand research firm.