Food insecurity—inconsistent access to nutritious food that meets daily needs—has been a persistent problem in the United States for many years. In Minnesota alone, approximately 900,000 people lack sufficient access to healthy food, including 200,000 children in low-income neighborhoods.
One cause of food insecurity is a lack of nearby full-service grocery stores. This is a particular concern in Minnesota, which has fewer grocery stores per capita than most other states.
One way to fill this gap is through mobile markets, which now operate in dozens of cities across the country. These markets use refrigeration-equipped buses, trucks, semi-trailers, or other vehicles to bring affordable, healthy food directly to communities in need. Mobile markets can particularly benefit people who don’t live close to a grocery store or who lack consistent access to a car.
Because many mobile markets are nonprofits, it’s crucial that they operate efficiently to remain financially viable. With funding from CTS, U of M researchers from the Department of Industrial and Systems Engineering (ISyE) partnered with local nonprofit Twin Cities Mobile Market (TCMM) to better understand mobile markets’ unique challenges and help improve their operational efficiency.
“When I first heard about mobile market programs, I thought they were a great idea,” says Yiling Zhang, ISyE assistant professor, CTS scholar, and study lead. “I suspected they faced interesting and important operations research questions. As I learned more about mobile markets, I found out that was indeed the case.”
TCMM, a program of local nonprofit The Food Group, has operated in the Minneapolis–St. Paul metro area since 2015. In addition to providing fresh produce, the market offers culturally connected foods focused on the preferences of Indigenous, Latino, African, and Asian communities, ensuring that residents from different backgrounds have access to familiar and nutritious food options.
The research team focused its efforts on examining vehicle routing and food stock assortment planning. “[These issues] are classical operations research problems,” says ISyE professor William Cooper, a member of the research team. “They intersect in a fascinating and unique way in mobile markets.”
The team developed a quantitative modeling framework for deciding which mobile market stops should be served on a single route while also determining what products to load onto the vehicle before it departs from its depot. Often, a vehicle will operate on a different route each day of the week. Depending on the population demographics near the stops on a particular route, different types of food might be more or less suitable for stocking that day.
Decisions about what locations to visit and what products to stock should be informed by estimates of demand from nearby communities, the researchers say. This demand is influenced by a variety of factors, including population-wide measures of demographics, mobility, and income; distance to nearest grocery stores; availability of community partners to help publicize mobile market services and schedules; and simple day-to-day variability.
By optimizing routes and product assortments, the team’s quantitative modeling approach may allow mobile grocery markets like TCMM to operate more sustainably and efficiently.
“This approach not only improves operational efficiency but also highlights the significant potential of mobile markets in improving food accessibility,” Zhang says.
This project was supported by CTS seed funding. Awarded biennially, this funding aims to help CTS scholars develop expertise in emerging areas and foster strategic relationships that position them for future funding opportunities.
—Adapted from content contributed by Yiling Zhang and William Cooper.
