But in the booming city of Rio de Janeiro, a luxury hotel has been turning trash into treasure for more than a decade, long before food waste was at the forefront of anyone's mind.
The glamorous Belmond Copacabana Palace — you know, the place where you might see Madonna or Mick Jagger hanging off the balcony — was among the country's first hotels to implement a restaurant waste-management system in 2008. Today, Copacabana Palace recycles more than 1,800 gallons of cooking oil and composts nearly all of its food waste, but not before crushing it to reduce its volume by 88 percent.
For many hotels, simple knowledge of the issue has resulted in greater observance from staff and ultimately, less waste.
When Soneva Fushi, a luxury resort in the Maldives, conducted a comprehensive food waste audit in 2016, employees sorted, weighed and recorded waste for a full week, ultimately establishing exactly how much food was wasted per guest down to the gram.
"I think part of the benefit of a detailed audit like this is that it increases everyone's mindfulness about what they are doing with food," says Gordon Jackson, the manager of the resort's "Waste-to-Wealth" initiative. "This has really helped everybody throughout the food and beverage team and the organization as a whole just to think about what they are doing."
Since the audit, the resort has seen a 50 percent reduction in the amount of waste sent to compost.
While it's easier for large hotels and resorts to fund audits and enlist comprehensive waste-management systems, smaller properties have found low-cost ways to reduce their environmental footprint, too.
When Anita Ritter opened her Island Hideout resort in Koh Yao Noi, Thailand, a year and a half ago, she was shocked by how challenging waste management was on her small, sleepy island, but a few innovative ideas have brought the resort's food waste to almost zero.
Ritter composts much of her property's organic waste to use as fertilizer, but she's found uses for compost byproducts too. "Compost juice," sometimes called bokashi, gets a new life as a cleaning fluid used at the resort. "It is a very efficient cleaner for clogged drains, perfect to clean toilets and sinks, and is a very good odor remover," she says. Leftover Kaffir limes, used in the property's homemade limeade, are repurposed in cleaning products.
"It helps give other islanders something to think about," Ritter explains. "As we use and reuse things, it gives us some social engagement status."
In May, I experienced one hotel's efforts firsthand, as I stood on the roof at ITC Maurya, a hotel in Delhi. It was more than 100 degrees outside and flies swarmed above vats of leftover naan and curry from the hotel's five restaurants, including Bukhara, arguably the world's most famous Indian restaurant. Next to the putrid mix stood a stainless steel tank, full of, in a sense, money — all in the form of decaying, rotting food.
That pricy leftover food — the hotel produces more than 1,300 pounds of it per day — was in the process of being converted to biogas, a methane and carbon dioxide mix that's a result of decomposing food. Ultimately, the resulting biogas powers the staff cafeteria. The hotel also collects around 100 pounds of waste from the community each day, using the same process to convert it into fuel.
ITC Maurya's BioUrja plant was a more significant investment than reusing lime peels and bokashi. The plant, which consists of a giant digester, a pressure vessel, scrubbers, and an automation panel, was installed in June 2016 and cost around 45 lakh, or roughly $65,000. Still, the hotel expects the project to break even in about four years.
In the meantime, the digester will chug along, reducing waste one bowl of leftover dal at a time.
Copyright 2018 NPR.