A team of Hong Kong scientists say they have found a way to transform food waste into laundry detergent, plastic ingredients, and a host of everyday products, in a discovery that may ease pressure on the city's bulging landfills.
Products from the "biorefinery" could even generate income, according to team leader Dr Carol Lin, a visiting assistant professor at City University. She unveiled details of the project in the United States last week at the 244th National Meeting and Exposition of the American Chemical Society in Philadelphia.
"We are developing a new kind of biorefinery, a food biorefinery, and this concept could become very important in the future, as the world strives for greater sustainability," she said. "Our new process addresses the food waste problem by turning trash into treasure, such as detergent ingredients and bio-plastics, which can be incorporated into other useful products."
The biorefinery process involves blending food waste with a mixture of fungi that excrete enzymes to break down carbohydrates into simple sugars. The blend is fermented in a vat where bacteria convert the sugars into succinic acid. Succinic acid can be used to make a range of products - from laundry detergent to plastics and medicine.
The team received a HK$518,000 grant from Hong Kong's Innovation and Technology Commission last year, and the work is due to be completed next August.
Food waste from Starbucks in Hong Kong and drink-maker Vitasoy International is being used in the testing.
In addition to providing a sustainable source of succinic acid, the technology could yield numerous environmental benefits, Lin said. Starbucks Hong Kong alone produces nearly 5,000 tonnes of food waste every year.
At present, this waste is incinerated, composted or disposed of in landfills. Lin's process could convert the waste into useful products. She has transformed food waste from CityU's cafeteria and other mixed food wastes into useful substances using the technology. The process could become commercially viable on a much larger scale with additional money from investors. "In the meantime, our next step is to … scale up the process," she said.