The key to reducing food waste on college campuses may be a reduction in the abundance of food choices many of them offer.

An expert team of researchers from schools including Rice University, Stanford University, Lebanon Valley College and several University of California campuses has concluded what pushes food waste in college university cafeterias — how much food they put on their plates, their familiarity with the menu and how much they like or dislike what’s served.

The findings, which were announced in a press release last week, were published in the journal Foods last month.

For the study, researchers surveyed students at five colleges and universities from the Menus of Change University Research Collaborative (MCURC) during the spring and fall 2019 semesters. They did so to evaluate food types, diner confidence and diner satisfaction. Photos that were taken by the diners before and after eating measured how much food they picked up and what went to waste.

“Diners were intercepted at their dining halls and asked if they wanted to participate in a study about food choices and satisfaction, but the objective of investigating food waste behavior was not disclosed,” the authors wrote.

Results showed that food waste was related to how much food diners put on their plates, how satisfied they were with their meals and the frequency with which they visited dining commons. Students who were pleased with their food tended to waste less of it. Those who visited the commons most often also tended to waste less because they were more familiar with the offerings and more confident in their decisions on what to eat.

Although foods such as fruits, vegetables or plant proteins didn’t occupy as much space on plates as dishes such as stir-fry, sandwiches, animal proteins and grains or starches, the food categories didn’t have noticeably different food wastage levels. Mixed dishes such as stir-fry and sandwiches, took up the most plate space of all the food types, however.

“Future studies could investigate other recruitment methods that reduce selection bias for a more representative sample of food waste behaviors,” the team concluded. “Researchers should also be mindful of survey design to prevent missing data whenever possible. Questions should be designed with data analysis methods in mind to avoid having to convert continuous data to categories. Building questions off key factors from existing behavior literature could help capture more variation and increase model fit.”