Cub is adding 24-hour service at 11 stores, as demand for groceries and essential household items continues to be strong during the coronavirus outbreak.

Thirteen stores already are open round the clock, the grocery company said.

"Consumers expect grocery stores to be there for them, and in times of a natural disaster, we're the last to close and the first to open," said Mike Stigers, chief executive of Cub. "That's a responsibility we take seriously, and that's why our work is essential now."

The extended openings will be staggered. Locations in Apple Valley, on Lyndale Avenue in Bloomington and Plymouth changed their hours Sunday. Seven more will open this coming Sunday. The Brooklyn Park North and St. Anthony stores will begin extended hours May 3.

For shoppers who worry that longer hours can make cleaning more difficult in a store that never closes, Stigers said that expanding the number of locations operating 24 hours increases social-distancing options for customers and provides additional shopping opportunities to first responders and medical personnel who work varied shifts.

"The commitment to safety of our customers and associates is the same high level at our 24-hour stores as it is our other stores," he said. "Over the course of this pandemic, we have enhanced our food safety and cleaning protocols at each store with great success, including the 13 stores that have maintained 24-hour operations. This is evident in the continued high marks we receive on food safety and other third-party audits throughout this crisis."

On March 17, 13 stores including Uptown Minneapolis, Blaine North and Chanhassen changed to 24 hours.

Cub's decision to expand hours at select stores runs counter to the trend. In early February, Hy-Vee officials announced that none of its 240 stores in eight Midwestern states would stay open after midnight. Supermarket chains such as Wegmans, Walmart, Albertsons and Kroger also started reducing hours before that, as did discount stores and pharmacies.

After the coronavirus struck, many supermarkets reduced their hours even more, including some Cub stores.

Before the pandemic, all Cub stores were open 24 hours with exception of some outside-the-metro locations and a few urban spots. "Maybe only five weren't 24 hours and their hours varied," said a United Natural Foods Inc. spokesman. Eden Prairie-based Supervalu, which owned Cub, was purchased by UNFI in 2018.

Besides Cub, about a dozen Walmart stores in the Twin Cities area also are open 24 hours. Cub added 24-hour service at its pharmacies in the Maple Grove store on Wedgewood Lane and the St. Paul Midway store.

Stillwater-based Cub was founded in 1968, and Cub operates 78 stores in Minnesota and one in Illinois.