With soup and vegetables flying off supermarket shelves to feed stay-at-home consumers, canneries are bustling — and they really need metal containers.

The big General Mills plant that turns out cans of Progresso soup is still operating 24 hours a day, seven days a week, just as it was before the virus hit. It employs 1,000 people and is hiring to fill 50 openings.

“I drove by the other day and the parking lot was full of cars, trucks coming and going,” said James Hark , a manager of an auto-body shop and the mayor of Hannibal, Missouri.

Someone has to make all those cans. The surge in demand for processed foods like canned soups and vegetables during the pandemic has rippled through the food industry’s supply chain. Makers of metal containers have had to speed up production to keep pace.

Silgan Holdings, a maker of metal and plastic containers for consumer goods with more than 50 plants across the country, reported record first-quarter earnings, in part because of a jump in demand for cans.

In a conference call, Silgan Chief Executive, Anthony J. Allott, said the company expected demand for canned goods to remain strong for some time since many people would continue to eat and entertain at home in the months ahead.

Another big maker of food and beverage cans, Crown Holdings, went into the year planning to increase production in the U.S., and the virus has only added urgency to the effort. Crown’s website lists 81 open production jobs at its 25 U.S. plants, some for a third production line being set up at a factory in Nichols, New York.

“We can sell every can we can make,” said Thomas Fischer, Crown’s vice president for investor relations and corporate affairs.

Acquiring the metal hasn’t been a problem. Despite the tariffs on imported steel and other metals, steel prices have eased this year. Moreover, recycling provides can producers with a reliable source — about 71% of steel food containers are recycled, according to the Can Manufacturers Institute.

Smaller suppliers are busy as well. In Rolling Meadows, Illinois, Apex Tool Works makes the machines and tools that produce metal cans and lids.

“We are actually swamped,” said President Mike Collins, whose family has run the company for 101 years. “The soup shelves are practically empty in the supermarkets, so our customers can’t make the stuff fast enough, and they’re running through their tooling very quickly.”

Collins said that he would like to add to his staff of 42, but that workers with the required machine and metalworking skills were difficult to come by. “It was like that even before the virus, so we haven’t hired in a while,” he said.

The food business is normally steady. But the surge in sales of canned and other packaged foods, when other transportation companies and vegetable producers have been knocked off stride by the virus, has forced manufacturers into a state of high alert.

For years, sales of soup and other canned foods have been declining slowly, as Americans gravitated toward fresh produce and other options often seen as more nutritious.

But lockdown orders have made shoppers cut down on trips to the supermarket and stock up on long-lasting items. The food industry has a name for this type of consumer behavior — “pantry-loading.”