Every day, millions of Americans drink Starbucks coffee. Millions of other Americans drink some other kind of coffee. No matter where they're coming from, there are a lot of coffee grounds produced every single morning.
At the end of the day, those grounds get thrown out - along with whatever stale baked goods they couldn't sell. In Hong Kong alone the chain throws out 5,000 tons of grounds and baked goods every year. But a new initiative hopes to salvage those waste products and turn them into something useful. Carol Lin is leading a team to design a biorefinery that could turn grounds and crumbs into plastics, laundry detergent, and all sorts of other products.
"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," Lin said in the press release. "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."
The press release describes, briefly, how the refinery works:
Lin described the food biorefinery process, which 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. Succinic acid topped a U.S. Department of Energy list of 12 key materials that could be produced from sugars and that could be used to make high-value products - everything from laundry detergents to plastics to medicines.
If the biorefinery works, it could remove millions of tons of trash from landfills, keep pollutants out of the atmosphere, and reduce the amount of land dedicated to garbage. But for it to work, they'll need funding, and testing, and planning. In the meantime, there are lots of things you can do with your own, personal coffee grounds.