'Closed loop' urban farm in Queenstown tackles food waste with insects

'Closed loop' urban farm in Queenstown tackles food waste with insects

03:23
As the Government ramps up efforts to reduce food waste and raise awareness of the problem, one urban farm in Singapore has been trying to lighten this load with the help of an insect.

SINGAPORE: As the Government ramps up efforts to reduce food waste and raise awareness of the problem, one urban farm in Singapore has been trying to lighten this load with the help of an insect.

Set up earlier this year, Citizen Farm in Queenstown has been using the black soldier fly to help grow its vegetables, as food for its fish and to help tackle food waste - the first in Singapore to incorporate these insects as part of farming practice.

The "closed loop" farm runs on a circular economy approach, by feeding the insect larvae with food waste from restaurants and supermarkets, turning this into nutrient-rich fertiliser.

Once the larvae transform into pupae, the insects are fed to jade perch fish which the farm rears. The fish subsequently secrete waste that becomes fertiliser for its vegetables.

Leftover agriculture waste - or produce that cannot be sold - is fed to the larvae, which then produces waste that becomes fertiliser.

The black soldier fly’s larvae feed on food waste, turning it into nutrient-rich fertiliser. (Photo: Wendy Wong)

The farm currently produces around 150kg of vegetables and fish a month, and goes through the same weight of food waste a day for its insect farm, which currently houses about 10kg of the black soldier fly's pupae.

According to head of Citizen Farm Darren Ho, the fly is also "easy to manage" as it does not transmit diseases, possesses a short life cycle of about six weeks and is a "shy insect" as it avoids human habitats.

The larvae transform into pupae, which are used as fish feed. (Photo: Wendy Wong)

Singapore generated 791,000 tonnes of food waste last year - about two bowls of rice daily - and this is set to grow along with the country's size and affluence.

Mr Ho told Channel NewsAsia that the purpose of such farming is to look at waste as a "resource" instead.

"The purpose of closed loop farming is to look at waste as a resource which we can then utilise to be looped back into our food cycle," said Mr Ho. "Food waste is something Singapore has in copious amounts."

"It is an issue to take them (food waste) out of the equation - so why don’t we take that to put it back into the food system through urban farming today, as urban farming becomes a lot more widespread in our economy?"

There are also wider benefits to running such a closed loop system in Singapore as opposed to conventional farming, according to Professor William Chen, the director of the food science and technology programme at Nanyang Technological University.

Benefits include cutting out the need to add chemical fertilisers to the soil and saving on the cost of fish feed, which can contribute to up to 50 per cent of a farm's operating costs, said Prof Chen.

"In Singapore we have very limited natural resources. We only allocate less than 1 per cent of land for agriculture and we import 90 per cent of food," said Prof Chen. "So closed loop farming provides a very attractive alternative in terms of sustainability of food production, because we rely less on land and use less water and energy."

"Therefore this actually contributes significantly to our goal in enhancing food security in Singapore."

He noted that the technology was not a new one that had come "out of nowhere" but one that had been used in neighbouring countries such as Indonesia and Thailand for more than a thousand years.

"(For example), in rice paddy fields, the farmer will keep the ducks or fish. So it’s already closed loop because the fish would take the discharge from the duck and the fish discharge will become fertiliser for the rice," he said.

The adult black soldier flies are kept in an enclosed space and lay eggs. (Photo: Wendy Wong)

Citizen Farm said it has plans to sell the insect as pet food and animal feed in the near future if this is approved by the authorities.

"The insect is very versatile – they can eat virtually anything including food waste," Prof Chen said. "The insect has similar nutritional profile as other animal proteins. So the insect grow on this food waste can be nicely fit into this closed loop farming practice."

 

Source: CNA/nc

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