Menus Subscribe Search

Bananas Aweigh

• March 08, 2010 • 5:00 AM

The Navy looks at new technology for keeping produce fresh during lengthy voyages; see-through salad era may be over.

Justin Nassiri spent five years as an engineer in the Navy, living on submarines that would remain underwater for two or three months at a time. Although the Navy’s cooks would make sure to stock enough supplies for the trip, after about two or three weeks, the bowls of fresh fruit would be down to just a couple of green apples. And the lettuce in the salads would begin to look translucent from having been frozen and thawed.

Nassiri says on long watches, during which he’d stare out at the water through a periscope for hours at a time, he and his colleagues would sometimes play a game in which they fantasized about what they missed most. Nassiri says his list always included sushi, fruit and vegetables.

“I’d actually have daydreams of fresh vegetables — celery, radishes, anything,” Nassiri said. “It was really impressive what the cooks could do, but as ingenious as they were, you can’t fight nature. After three weeks, the salad would be see-through.”

Nassiri isn’t the only one daydreaming. Naval officials have been working with food scientists for the last two years to find ways to make fresh fruits and vegetables last longer. It’s not just about keeping sailors happy and healthy. It’s about waste. A few years ago, one naval official said his service was spending about $26 million a year on fresh fruits and vegetables, and then throwing out about $3 million because it had spoiled.

Fruits and vegetables respire like human beings. But when humans use energy, they replenish their reserves by eating. Fresh fruits and vegetables, on the other hand, have been separated from the plants on which they grew and can’t generate new energy reserves.

The trick to keeping fruits and vegetables alive longer, then, lies in slowing down the amount of energy they expend, and that is done by reducing their metabolism or respiration rate — the rate at which they take in oxygen and release carbon dioxide. That’s usually achieved in two ways: by keeping the produce at a low temperature — 32 to 55 degrees Fahrenheit, depending on the fruit — or by modifying the atmosphere in which fruits and vegetables are stored.

Navy officials are working with a food technology company in California, Apio Inc., which has a product, BreatheWay, that controls the ratio of oxygen to carbon dioxide moving in and out of a package. The ratio is regulated via a membrane placed over a hole or window in the packaging. The membrane helps maintain an appropriate ratio of oxygen and carbon dioxide inside the package, depending on the type of fruit or vegetable being stored. The oxygen level in the air of an ordinary room, for instance, might be 20.8 percent, while the oxygen inside a modified-atmosphere package might be as low as 3 percent. The level of carbon dioxide inside the package might be 4 to 6 percent, while it might be near zero percent outside.

BreatheWay also has a temperature switch that increases or decreases permeability in the packaging, depending on the temperature at which the package is stored. By slowing down how quickly the produce uses its energy reserves, scientists can make it live longer. Keeping fruits and vegetables healthy also inhibits the growth of organisms that decay produce.

“When you harvest a fresh vegetable or fruit, it has a reaction to being separated from the sustaining tree or plant, and that wound makes it respire faster. It’s panicking, if you will,” says Cali Tanguay, business development manager at Apio. “You’re trying to create an environment that’s as moderate as possible.”

In trying to determine which technology to use, the Navy conducted food-freshness tests on two aircraft carriers — the USS Ronald Reagan on the West Coast and the USS George H.W. Bush on the East Coast — in February and October of 2008, using broccoli crowns, cantaloupe, honeydew, iceberg and romaine lettuce, bananas and tomatoes. The Navy chose products that were in high demand by sailors, that seemed to respond well to the technologies being tested and that were not easy to replace with canned or frozen versions.

The results were a smashing success, naval officials said. The cases lined with Apio’s product enabled the Navy to extend the shelf life of fresh fruits and vegetables greatly, according to Gerald Darsch, director of the Department of Defense’s Combat Feeding Directorate. Lettuce, for instance, lasted 70 percent longer, cantaloupe 150 percent longer, and broccoli a whopping 300 percent, Darsch said.

“I traveled with one of my co-workers, and she got a big hug from the supply officer on the USS Reagan,” Darsch said. “They noticed they had bananas to eat well into the deployment. In the past, they barely got away from the pier before the bananas were gone.”

The Navy conducted another test in November on fruits and vegetables sent in commercial shipments to military bases in Guam. It created three scenarios: The first container was simply refrigerated, with nothing done to the atmosphere inside. The second container was refrigerated and filled with a specific mixture of oxygen and carbon dioxide. The third container was refrigerated, and the individual cases of produce were lined with Apio’s product. At the end of 38 days, only 58 percent of the broccoli in the first container was usable. In the second container, 79 percent of the broccoli was good. And in third container, which used Apio’s technology, 94 percent of the broccoli was edible.

But if early tests have been successful, logistics still have to be addressed. The military can be highly secretive about the locations of its ships and submarines. Naval officials wouldn’t even disclose the locations of the aircraft carriers on which the produce technology was tested. Sometimes, officials don’t know where a ship will be in a week.

It was just these kinds of logistical issues that made it difficult to test the technology on submarines, even though they’re likely to be one of the biggest users of the products. The problem that makes it difficult for them to stock up on fresh produce — they move out of reach of ports and supply ships for extended periods of time — also made it difficult to get nonmilitary personnel on board for product testing, which is why the trials were conducted on aircraft carriers. There are also problems with space — particularly on submarines — and loading processes, which can result in produce being left to sit out on a hot dock for hours, losing valuable shelf life.

“The bottom line is, this all adds a step of complexity,” Apio’s Tanguay said.

The military has also been looking at technologies to remove ethylene gas from fruit and vegetable packaging. Produce gives off this gas naturally as it ripens, and ethylene signals fruits and vegetables to ripen; too much makes produce ripen too quickly and rot.

The Army has been testing a product developed by a Massachusetts-based company, Primaira LLC, which uses an electrical device to convert ethylene gas into water and carbon dioxide. The product was put into a shipping container with broccoli and apples, and after seven days, the broccoli had lost only 20 percent of its firmness, compared to a 60 percent loss without Primaira’s technology, says Karen Benedek, managing partner at Primaira. Naval officials plan to test the Primaira device this year and hope to use it on aircraft carriers, where, if the new freshness technologies work, see-through salad will be deep-sixed, rather than eaten.

Sign up for our free e-newsletter.

Are you on Facebook? Become our fan.

Follow us on Twitter.

Add our news to your site.

Caren Chesler
Caren Chesler has been a journalist for 20 years. Her work has appeared in The New York Times, Salon.com, The New York Daily News, Bloomberg Business News, Investor’s Business Daily and The European, among other publications. She was born on Long Island, has lived in London and Budapest, and now divides her time between Harlem, N.Y., and Ocean Grove, N.J.

A weekly roundup of the best of Pacific Standard and PSmag.com, delivered straight to your inbox.

Recent Posts

July 25 • 4:00 AM

Arizona’s Double-Talk on Execution and Torture

The state is certain that Joseph Wood’s death was totally constitutional. But they’re looking into it.


July 24 • 4:00 PM

Overweight Americans Have the Lowest Risk of Premature Death

Why do we use the term “normal weight” when talking about BMI? What’s presented as normal certainly isn’t the norm, and it may not even be what’s most healthy.


July 24 • 2:00 PM

California’s Lax Policing of the Fracking Industry Has Put the Drought-Stricken State in a Terrible Situation

The state’s drought has forced farmers to rely on groundwater, even as aquifers have been intentionally polluted due to exemptions for the oil industry.


July 24 • 12:00 PM

What’s in a Name? The Problem With Washington’s Football Team

A senior advisor to the National Congress of American Indians once threw an embarrassing themed party that involved headdresses. He regrets that costume now, but knows his experience is one many others can relate to.


July 24 • 11:00 AM

How Wildlife Declines Are Leading to Slavery and Terrorism

As wildlife numbers dwindle, wildlife crimes are rising—and that’s fueling a raft of heinous crimes committed against humans.


July 24 • 10:58 AM

How the Supremes Pick Their Cases—and Why Obamacare Is Safe for Now

The opponents of Obamacare who went one for two in circuit court rulings earlier this week are unlikely to see their cases reach the Supreme Court.



July 24 • 9:48 AM

The People Who Are Scared of Dogs

While more people fear snakes or spiders, with dogs everywhere, cynophobia makes everyday public life a constant challenge.


July 24 • 8:00 AM

Newton’s Needle: On Scientific Self-Experimentation

It is all too easy to treat science as a platform that allows the observer to hover over the messiness of life, unobserved and untouched. But by remembering the role of the body in science, perhaps we humanize it as well.


July 24 • 6:00 AM

Commercializing the Counterculture: How the Summer Music Festival Went Mainstream

With painted Volkswagen buses, talk of “free love,” and other reminders of the Woodstock era replaced by advertising and corporate sponsorships, hippie culture may be dying, but a new subculture—a sort of purgatory between hipster and hippie—is on the rise.


July 24 • 5:00 AM

In Praise of Our Short Attention Spans

Maybe there’s a good reason why it seems like there’s been a decline in our our ability to concentrate for a prolonged period of time.


July 24 • 4:00 AM

How Stereotypes Take Shape

New research from Scotland finds they’re an unfortunate product of the way we process and share information.


July 23 • 4:00 PM

Who Doesn’t Like Atheists?

The Pew Research Center asked Americans of varying religious affiliations how they felt about each other.


July 23 • 2:00 PM

We Need to Start Tracking Patient Harm and Medical Mistakes Now

Top patient-safety experts call on Congress to step in and, among other steps, give the Centers for Disease Control and Prevention wider responsibility for measuring medical mistakes.


July 23 • 12:19 PM

How a CEO’s Fiery Battle Speeches Can Shape Ethical Behavior

CEO war speech might inspire ethical decisions internally and unethical ones among competing companies.


July 23 • 12:00 PM

Why Do We Love the ‘Kim Kardashian: Hollywood’ Game?

It’s easy enough to turn yourself into a virtual celebrity, complete with fame and mansions—but it will likely cost you.


July 23 • 11:49 AM

Modern Technology Still Doesn’t Protect Americans From Deadly Landslides

No landslide monitoring or warning systems are being used to protect vulnerable communities.


July 23 • 10:00 AM

Outing the Death-Drug Distributors

Calling all hackers: It’s time to go Assange on capital punishment.


July 23 • 8:00 AM

The Surprising Appeal of Products That Require Effort to Use

New research finds they enable consumers to re-establish a feeling that they’re in control of their lives.



July 23 • 6:00 AM

How the Other Half Lifts: What Your Workout Says About Your Social Class

Why can’t triathletes and weightlifters get along?


July 23 • 5:02 AM

Battle of the Public Intellectuals: Edward Glaeser vs. Richard Florida

On gentrification and housing costs.


July 23 • 4:00 AM

Our Fear of Immigrants

Why did a group of fourth graders rally in support of an undocumented classmate while the citizens of Murrieta, California, tried to stop immigrant children from entering their town?


July 22 • 4:00 PM

Can Meditation Really Slow Aging?

Is there real science in the spiritualism of meditation? Jo Marchant meets a Nobel Prize-winner who thinks so.



Follow us


Subscribe Now

How Wildlife Declines Are Leading to Slavery and Terrorism

As wildlife numbers dwindle, wildlife crimes are rising—and that's fueling a raft of heinous crimes committed against humans.

How a CEO’s Fiery Battle Speeches Can Shape Ethical Behavior

CEO war speech might inspire ethical decisions internally and unethical ones among competing companies.

Modern Technology Still Doesn’t Protect Americans From Deadly Landslides

No landslide monitoring or warning systems are being used to protect vulnerable communities.

The Link Between Carbs, Gut Microbes, and Colon Cancer

Reduced carb intake among mice protected them from colon cancer.

The New Weapon Against Disease-Spreading Insects Is Big Data

Computer models that pinpoint the likely locations of mosquitoes and tsetse flies are helping officials target vector control efforts.

The Big One

Today, the United States produces less than two percent of the clothing purchased by Americans. In 1990, it produced nearly 50 percent. July/August 2014

Copyright © 2014 by Pacific Standard and The Miller-McCune Center for Research, Media, and Public Policy. All Rights Reserved.