Starbucks’ food waste sent to a ‘food biorefinery’ has been turned into bioplastics that can be used in packaging thanks to Hong Kong researchers.
The biorefinery changed food waste such as spent coffee grounds and stale bakery goods from the retail chain in Hong Kong into succinic acid for making plastics.
Carol S. K. Lin led the research team who developed successful laboratory testing of a biorefinery intended to change food waste into plastics and other everyday products.
Their report on the project came at the 244th National Meeting & Exposition of the American Chemical Society.
Biorefineries convert corn, sugar cane and other plant-based material into a range of ingredients for bio-based fuels and other products.
How it works
The process involves blending the baked goods with a mixture of fungi that excrete enzymes to break down carbohydrates in the food into simple sugars.
The blend then goes into a fermenter, a vat where bacteria convert the sugars into succinic acid.
The idea formed last year between representatives of the nonprofit organization ‘The Climate Group’ and Lin at her laboratory at the City University of Hong Kong.
The group asked about applying Lin’s biorefinery technology to one of its members, Starbucks Hong Kong, so researchers would collect the waste weekly from the retail outlet.
Estimates say that Starbucks Hong Kong produces nearly 5,000 tons of used grounds and unconsumed waste bakery items every year.
Currently, it is incinerated, composted or disposed of in landfills but the process could convert it into useful products
Carol Lin, a visiting assistant professor in the school of energy and environment at the City University of Hong Kong, told FoodProductionDaily.com the next step in the project is to scale it up.
“A good amount of bio-plastic can be created from waste and the amount of food waste is a concern, a pilot plant takes time to build the facility up.
“We did it on a laboratory scale and now we needs to scale it up as there are other firms in Hong Kong interested."
Lin added the researchers would go to Starbucks outlet once a week, the waste would be collected from the outlet and the next day it would be in the laboratory, ensuring the work could be done near to where the waste was produced.
“It is a good strategy to solve imminent issues in Hong Kong with landfill sites filling soon and I am interested to see the effectiveness of solving these waste issues.”
Lin added that funding has been applied for to test this idea in a pilot-scale plant in Germany and with more funding, it could be rolled out in other countries and for other companies.