'Magic' process turns kiwifruit into gold

Dr Martin Markotsis says Scion is checking if it can get a patent for the 'spife' utensils. Photo / Alan Gibson

New Zealand researchers have cracked what seems like modern-day alchemy, transforming one kiwifruit into 100 plastic spoons and Rotorua's sewage into electricity.

Scion, a Crown research institute in Rotorua, has developed technology to make many products out of organic materials and waste.

It has created compostable bioplastics from kiwifruit waste, which will be used to make combined spoon and knife utensils known as "spifes".

Researcher Martin Markotsis said the secret was a chemical process that made kiwifruit melt like plastic in standard factory equipment.

"We do a 'reactive transformation' - that sounds pretty magical, doesn't it? We're checking whether we can get a patent.

"If we say too much, we can't patent it," Dr Markotsis said.

Small batches of prototypes have been made, mixing different amounts of kiwifruit, corn and other secret, but organic, additives.

The project is now picking the best mixture - with the right strength and flexibility - and ramping up production to a commercial scale. One piece of fruit, about 90g, can make more than 100 of the utensils.

The utensils will be included in kiwifruit packages sold overseas by Zespri.

Dr Markotsis said other fruit could be put through the same process to make all sorts of plastics.

Scion Research this week also received a $1 million government grant to transform sludge from Rotorua's sewers into marketable products.

A pilot plant will be built by the beginning of next year, turning biosolid waste headed for landfill into industrial chemicals and energy-rich gases such as methane. Heat and gases released by the process will generate electricity to help power the plant.

More than 20 tonnes of sludge pouring into landfill every day will be diverted, saving up to $900,000 a year in costs - a total of $4 million a year in benefits to the town.

The technology will transform up to 97 per cent of the sludge. Another innovation at the research centre is the "biopeg", tent pegs that can be left in the ground to eventually decompose into the soil.

The global market for bioplastics is expected to grow 20-fold in a decade, with overseas rivals building mobile phones from cashew nut shells and corn.