A new "biorefinery" would transform old coffee grounds and stale baked goods into ingredients for plastics and detergent.
Who's got tons of old coffee grounds headed for the trash? Starbucks. And who's got great ideas for repurposing waste? Scientists. It's a promising match.
A team of researchers at the City University of Hong Kong are working on a new "biorefinery" that would turn food waste into something useful, and it's been getting funding from Starbucks Hong Kong, which produces 5,000 tons of spent grounds and bakery waste each year.
According to a press release, the biorefinery (above) uses a mixture of fungi, which excrete enzymes that break down carbohydrates (like the ones in those coffee grounds) into simple sugars, which then go into a fermenter to become succinic acid. That succinic acid can then be used as an ingredient in a wide variety of products, including detergents, bio-plastics, and medicines.
Carol S. K. Lin, Ph.D., explained that the biorefinery addresses a very real resource challenge:
Using corn and other food crops for bio-based fuels and other products may not be sustainable in the long-run. Concerns exist that this approach may increase food prices and contribute to food shortages in some areas of the world. Using waste food as the raw material in a biorefinery certainly would be an attractive alternative.\n
Not only does this process cut down on a burdensome waste stream, it also reduces air pollution by avoiding incineration.
Starbucks isn't using this technology yet—Lin says her team needs to do more work to make it scalable and ready for commercialization—but it's not hard to imagine how beneficial it could be for the coffee company and the city, especially given Hong Kong's looming waste problem.