Warning! Contents Under Extremely High Pressure Hyperbaric Pressure Chambers Aren’t Just for People, They’re for Food Too
What exploring the incredible water pressure found at the greatest depths of the ocean can tell us about a longer-lasting guacamole.
Why am I showing you a video of a tiny submersible that descended into the deepest part of the ocean fifty-one years ago?
Well, deep down at the bottom of the Mariana Trench, the weight of the ocean exerts pressure—eight tons per square inch—which is 1,000 times more pressure than it would take to make your eardrums explode. It’s about the same pressure as would be exerted by a full-grown male African elephant standing on the cross-section of two dimes.
When the kind of pressure found at the bottom of the ocean is applied to food, it destroys harmful bacteria, essentially doing to microbial cell walls what pressure would do to your eardrum. The process is already in place and manufacturers use it to extend the shelf life of guacamole, orange juice, shucked oysters, lobster, and luncheon meats, often without advertising this rather fascinating process.
I wrote about about high-pressure processing briefly for Wired magazine—and what’s almost as remarkable as the technology is the story of how it came about in the United States.
While the theory of air pressure dates to 1647 and 100,000 pounds per square inch of water pressure was first shown to extend the shelf life of raw milk in 1899, it wasn’t until an oysterman in Louisiana took some pipes destined for pressure testing oil wells in the Gulf of Mexico and cobbled together a oyster shucking contraption that high pressure processing really made its way onto the U.S. market.
In 1997, Ernie Voison had been tinkering around with building an oyster shucker for at least a decade, and his son Michael told me that after reading about high-pressure food processing machines in a European trade journal, Voison accomplished something oystermen had been trying to do for 30 years: He made a machine that popped open oysters. The pressure that forced opened up the bivalves also, coincidentally, could be used to remove Vibrio vulnificus, the pathogen responsible for almost all seafood-related illnesses.
It's a small silver lining, I know, but it's amazing that something good for oysters once came out of the offshore oil industry in the Gulf. And it's amazing that we've been able to replicate the intense pressure of the ocean depths on land.