Restaurants can help reduce food waste in landfills by offering compostable plates, cups and utensils, according to a new study by Eco-Cycle, a nonprofit zero-waste organization.

“Restaurants play a critical role in reducing and recovering food scraps, and composting is one of the fastest, most cost-effective solutions for reducing carbon pollution and reducing waste,” said Kate Bailey, Eco-Cycle’s policy and research director and one of the study’s authors along with Dale Ekart.

Offering compostable serviceware would make it easier for restaurant customers to help reduce food waste by composting their scraps and sorting it into the right bins, the study found. It noted that restaurants are recovering some food waste, but far too much still gets thrown out.

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“Less than 15% of restaurant food waste is collected for composting, and these efforts have primarily focused on collecting food scraps from the kitchen,” the study said. “However, on average, diners leave 17% of their meal uneaten, and more than half of these potential leftovers are not taken home. This means there is a large, untapped potential to recover food waste generated by diners through front-of-house composting programs that collect food scraps from customers.”

One of the keys to composting success, the study found, is for restaurants to simplify their serviceware by using durable plates, glasses and utensils or using all compostable serviceware. Nationwide, 85% of customers say they are willing to sort their waste after eating out if bins are provided.

However, for recycling and composting to succeed, the sorting has to be done properly. The study found that consumers struggled with how to sort materials when there were several different types of food serviceware. By contrast, those restaurants that used one primary type of serviceware — either durable, reusable plates and utensils or a fully compostable system — had higher rates of success. The result: more of what composters love (food scraps) and less of what composters hate (materials like non-compostable plastic that contaminates the compost).

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The quick-service restaurant with all compostable food serviceware performed well — meaning they captured most of their food scraps with very little contamination — as did the quick-service restaurant using all durable food serviceware, suggesting both of these approaches can be used successfully to capture food scraps for composting, the study found.

“This report is the first of its kind to demonstrate this can be done well and is worth doing,” Bailey said. “Food establishments are capable of very high diversion rates, making them a key partner in moving toward Zero Waste, reducing our carbon emissions and building healthy soils through composting.”