Company making animal feed and fertiliser out of food products that would have otherwise ended in landfill.

How do you stop truckloads of unsaleable food from going to the dump - and turn it into something useful? Put a few thousand piggies in the middle.

Each day at the Ratanui Development Company, near Feilding, two trucks deliver around 20,000 litres of whey, to be gobbled up by 8300 pigs.

This by-product of cheese-making - along with other foods such as bread, yoghurt, cheese and dog biscuits - make up about 40 per cent of its hungry hogs' diet.

"When you drill down on the volume of stuff that these pigs eat, it usually blows people away," farm director Andrew Managh said.


But more impressive is the idea of what this novel factory-to-farm approach could mean for recycling in New Zealand. The huge piggery is one of 23 farming operations partnered with Auckland-based EcoStock Supplies, which claims its unique business model could dramatically slash the burden on the country's landfills by millions of tonnes each year.

The business model begins at the factory doors of 225 food manufacturers mostly in the Auckland area.

EcoStock trucks take away surplus food stock, deemed unsaleable because they are past expiry dates, damaged, or had been incorrectly weighed or mixed.

The products are then used to make nutritionally balanced stock feed and fertiliser, and distributed to a select group of farmers under strict food security standards.

At Ratanui, many foods were also fed directly to the pigs - even cakes, sweets and fruit if they were lucky.

"After eating that, they tend to turn their nose up when they go back to a cream-based diet," Mr Managh said.

The farm also had its on-site facilities to up-cycle the products, and food not suitable for stock feed was composted to make a supplementary fertiliser.

Mr Managh even planned to use methane gas flares from the pigs' effluent ponds to generate electricity and hot water.


EcoStock also worked with dairy, beef and free-range chicken operations. "In a day, we'll handle 200 tonnes of product, seven days a week," EcoStock director Andrew Fisher said.

The business was growing and, if built up to its biggest potential, could ultimately strip as much as 2.2 million tonnes out of the total amount going to landfill each year, he said.

Last year, the company, in partnership with Ratanui. was a joint winner of the University of Auckland Business School Entrepreneurs Challenge, taking half of a million-dollar prize.

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