Oval plates could be key to reducing food waste, researchers say

University of Illinois scientists uncovered a simple change that could help reduce food waste in U.S. college dining halls – a setting the research team behind study named as the main culprit for food waste in the country.

Switching from round to oval platters with smaller surface areas can significantly reduce food waste in dining rooms, said Brenna Ellison, associate professor in the Department of Agricultural and Consumer Economics (ACE) and co-author of the study.

„Americans waste about 31 percent of the food available in retail stores and with consumers,” said Ellison.

“All-you-can-eat attitudes (common in dining rooms) are particularly challenging as there aren’t the normal incentives to reduce waste yourself. When you pay a fixed amount of money to go out to eat, you want your money’s worth. „

Ellison’s research team previously worked with University Housing in Illinois on a waste reduction awareness campaign.

„It wasn’t as successful as we expected,” she said. „That’s why University Housing wanted to find out if changing plates was a successful way to reduce waste.”

Thurman Etchison, assistant director of restaurants and equipment operations at the University of Illinois, said a 2016 waste study in campus dining halls found about 93.5 grams of wasted food per meal. That was 6,747 kilograms per week at six locations in dining rooms.

„When we think of food waste in our environment, it is important to note that it is not just the resources that are wasted making the food,” says Etchison.

“There is a lot of energy, water and work going into refrigerating, preparing, transporting and serving this food that is also wasted. If that weren’t enough, there’s also the wasted energy, labor, and water that goes into disposing of this food. The food we waste costs us more per pound than the food that is eaten. „

Ellison and co-authors Rachel Richardson, former PhD student at ACE, and Melissa Pflugh Prescott, Assistant Professor in the Department of Food Science and Human Nutrition, conducted the plate study in two University Housing dining rooms on the university campus. Both the round and oval plates were tested at each location, ensuring that the same menu was used for both plate types.

The researchers approached the guests after choosing their food and asked them to take a photo of the plate and weigh the food. Guests then completed a quick survey, and when they finished eating and returned their tray to the plate, the researchers took another photo and weighed the rest of the food.

The study included more than 1200 observations, and the researchers found significant reductions in food selection, consumption, and waste when diners used the oval plates. Overall, food waste fell from 15.8 percent of the foods selected for round plates to 11.8 percent for oval plates. That’s nearly 20 grams less food waste per plate, which is a lot for a dining room that serves thousands of meals, Ellison noted.

The research team believes that changing the plate type is a viable strategy to reduce food waste, although dining room managers must weigh the cost of buying new plates against the potential savings. However, combining the direct kick-start approach of smaller plates with an awareness campaign could be even more effective, the study’s authors claim.