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Can you flash freeze whole pig carcasses?

Minnesota pork plants sidelined by coronavirus outbreaks have begun euthanizing and disposing of thousands of pigs. One reader wondered whether they could just freeze the carcasses instead of wasting all that meat.

This would be challenging for two reasons.

“It’s not possible to do because of food safety and because of the capabilities of the plants,” said Dave Preisler, head of Minnesota Pork Producers Association. “But first and foremost because of food safety. And then second of all because the plants just don’t operate that way.”

Organs must be removed before pigs are frozen to prevent contamination, said Prof. Lee Johnston, a swine expert at the University of Minnesota Extension in Morris.

“If we just sacrifice the animal, remove the blood, we can’t freeze them at that point because [it has] got all these internal organs and the digestive tract with bacteria and so forth that are normally resident in there,” Johnston said. “So we need to get those out.”

This typically happens on a large assembly line, but closed plants don’t have workers to do that.

“It’s kind of a Henry Ford assembly line in reverse,” Johnston said. “You start with the whole pig and they take the pieces out.”

Even if you could remove the organs, there’s no place to freeze a large volume of whole pigs.

Pork plants have large refrigeration rooms with trolley systems for moving and storing thousands of pig carcasses, before they are sliced up into pork chops and other cuts. But they are not freezers.

“[The freezers] are designed for boxes of packaged retail cuts and those kind of things, and not for whole carcasses to be stored in,” Johnston said.

Preisler said plants generally have cooler capacity for one or two days worth of processing.

“There’s no place for them to go,” Preisler said. “And even if you were to move things off-site, to a freezer, freezer space in general is really tight.”