From pastry to plastic: Starbucks finds sweet spot for food waste

Editor's note: Rachel Nuwer originally wrote this piece for GE's ecoimagination blog.

Local Hong Kong Starbucks branches have teamed up with researchers to boil old baked goods down to their core chemical components in order to extract recycled ingredients used in plastics, laundry detergents and other ubiquitous products.

“We’d go collect bakery waste from Starbucks outlets once a week and process it in our lab to convert the waste into useful chemicals, like succinic acid and bioplastic,” says Carol S. K. Lin, a biochemical engineer at the City University of Hong Kong who led and presented the project at the 244th National Meeting and Exposition of the American Chemical Society.

“Succinic acid is a popular molecule, and there are already plants built in Europe, Thailand and the States,” she says.

Starbucks kicked off the experiment earlier this year with their “Care For Our Planet” campaign in Hong Kong. The coffee chain advertised charity sets of cookies and cups, and for each one sold Starbucks donated about $1 (HK $8) to the university for research support. By the end of the campaign, Lin’s school collected about $6,400. Along with a grant from the Innovation and Technology Commission, Lin had enough resources to perform a thorough investigation of the pastries’ recycling potential.

The goal is to find a use for the 1.3 billion tons of food waste that is dumped each year.

She and her colleagues used biorefinery technologies -- or the process of converting organic materials into bio-based products like animal feed, chemicals or biofuels -- to break down the pastries. To achieve this, they undertook a method called acid hydrolysis.

Photo of pastry and coffee provided by grynold via Shutterstock

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