HUDS Expands Artificial Intelligence System to Reduce Food Waste

Harvard University Dining Services has fully implemented Winnow, an AI-powered system that tracks and categorizes food waste, across all of Harvard’s residential dining halls and Annenberg.

HUDS began rolling out the technology across campus last spring following a pilot program last fall. As of September, Winnow had helped reduce food waste by 23,500 pounds, according to a report shared by the company.

The system uses a scale and overhead camera to weigh and photograph food scraps, before identifying individual food items using data from HUDS’ weekly menus. Then, the program generates daily and weekly reports that list dining halls’ top-wasted items by both volume and cost.

The reports allow the management of each dining hall to “get a snapshot” of which menu items yield the most food waste, Gina Sears, a development manager at Winnow said.

“The chefs can kind of make decisions on the fly the next day,” she added.

The technology has already prompted changes in the dining halls. In its yearly Learning Report released earlier this month, HUDS reported that chefs began preparing eggs in smaller batches after discovering they were discarding an average of 11.5 pounds a day. The change reduced its daily egg waste to 3.1 pounds.

Winnow representatives also regularly meet with the lead chefs of each dining hall and HUDS’ director of culinary operations to identify broader patterns in the data, Sears said.

With data and advising from Winnow, HUDS shortened its menu from a four-week to a three-week cycle over the summer, serving popular dishes more often and scaling back low-demand offerings.

Following the change, average food waste per meal fell 31 percent, from 2.12 ounces to 1.46 ounces per swipe, according to Winnow’s report.

“Every meal swipe that a certain dining hall or House receives for service during that day, we focus on, what is the normalized amount of waste? So, per swipe, how much are we wasting?” Sears said.

HUDS’ partnership with the AI technology builds on its latest efforts to make Harvard’s dining halls more sustainable. Last year, dining halls fully replaced single-use, compostable takeout containers with 4,255 reusable plastic containers, which students can check out. In September, the Green Restaurant Association named Harvard as North America’s “greenest university” for the third year in a row.

“HUDS is making meaningful contributions to campus waste reduction through initiatives like the Reusable Container Program and Winnow,” Courtney Forrester, Harvard’s waste reduction and compliance lead, wrote in a statement.

“Both programs align with the goals of Harvard’s Waste Stewardship Framework and demonstrate how waste reduction efforts can also deliver operational cost savings,” she added.

But some students said reducing food waste also requires changes in students’ own dining habits.

“I think it’s important to don’t take more than you can actually eat. If you want, you can always go back for more,” Alicia Y. Li ’30 said.

“That’s something that needs to fundamentally change in our student body, rather than only putting it as the responsibility of the HUDS workers to try and mediate a problem that we are, in effect, causing ourselves,” she added.