Coffee giant Starbucks in Hong Kong is testing out an innovative recycling process that turns old, stale baked goods and coffee grinds into bio-plastics and laundry detergent in an attempt to lessen its environmental footprint.
The project, led by scientists at the City University of Hong Kong, is being tested at a new food ‘biorefinery,' that diverts food waste and transforms it into viable, usable products.
The project was presented at a meeting of the world's largest scientific society, the 244th National Meeting & Exposition of the American Chemical Society in Philadelphia this week.
Like oil refineries which covert petroleum into fuel and other ingredients for use in consumer products, biorefineries transform corn, sugar cane, and other plant-based material into bio-based fuels and other products.
But using raw food staples to produce fuel has been a thorny subject, as environmentalists say it's a shortsighted solution that would drive up food prices and contribute to food shortages.
Recycling food waste, however, to make other viable consumer products has the potential of diverting tons of garbage from landfills and reducing the need to manufacture goods from virgin, raw sources, scientists say.
Starbucks Hong Kong produces about 5,000 tons of used coffee grounds and unconsumed baked goods that end up in the garbage bin every year. Currently, most of the waste is incinerated, composted or disposed of in landfills.
'How it works'
The food biorefinery process, meanwhile, involves blending the stale baked goods with a mixture of fungi that help break down the carbohydrates into simple sugars. The blend is then fermented in a vat where bacteria transform the sugars into succinic acid, a key material that's used to produce everything from laundry detergent, plastic, to medicine, scientists explain.
Baked goods have also been used to create livestock feed.
British supermarket chain Sainsbury's, meanwhile, is the largest retail user of anaerobic digestion technology which turns food waste into energy -- a process that has generated enough electricity to power 2,500 homes.
But it's not Sainsbury's only solution for unsold food. The grocery chain, like Tesco and Waitrose, also donates surplus food to homeless shelters and day centers for the elderly or vulnerable schoolchildren through food charity FareShare.
Gourmet sandwich chain Pret a Manger in the UK also donates leftovers from the day's sales to the homeless.