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Enthusiasts say new technology is the biggest thing since commercial canning

WASHINGTON—Some food-industry Ph.D.s sound as if they've been smoking something other than salmon.

They talk of orange juice that, after 12 weeks of refrigeration, tastes as good as fresh, of TV dinners that "deliver a gourmet restaurant experience," of bananas that don't turn black and of scrambled eggs for soldiers' rations that taste as if they were just cooked.

The secret, they believe, is a costly new high-pressure preservation technology. Only a few U.S. food processors use it today, but Martin Cole, the director of the National Center for Food Safety and Technology at the Illinois Institute of Technology in Summit, Ill., predicts that high-pressure preservation will be "the biggest thing in food processing since commercial canning."

Part of the argument for high pressure is that, when used on fruits, "flavors and vitamins are not degraded," according to Cole.

Tom Mertensotto, the marketing director for Perdue Farms' line of ready-to-eat products, seconds the claim. High pressure, which Perdue uses for its popular Short Cuts grilled chicken and grilled turkey, "does not change the texture, taste or nutritional values of our products," Mertensotto said.

The process, which uses pressure equal to the weight of two elephants standing on a dime, takes about 10 minutes. Vacuum-packaged food is dunked in tanks of water, the tanks are sealed, then more water is pumped in. As the water's pressure rises, compressing the food, it kills bacteria, enzymes and molds by breaking their molecular structures and popping their cell walls like blisters. Once the pressure's off, the food returns to its original volume and appearance.

Why isn't the food pulverized? It's all in the physics: As long as pressure is uniform on all surfaces of an object, it won't distort it. (Think of a grape inside a sealed water bottle. No matter how hard the bottle's squeezed, it doesn't crush the grape.)

The process may indeed enhance taste. In an informal blind tasting of deli meats, grilled chicken and guacamole preserved by high pressure and by chemical additives, 22 tasters assembled by Knight Ridder generally preferred foods treated the new way.

Even a cold-cut pro—Steven Loeb, the meat buyer for Loeb's Deli, a downtown Washington fixture since 1959—was mildly impressed. "This turkey tastes like turkey," he said. "Some doesn't, but this does."

High-pressure preservation has its downsides, however. It's too expensive for many products and still requires refrigeration. It doesn't work well on vegetables and discolors foods if the pressure is too high.

For all these reasons, processors tend to use the process on foods with high markups, such as deli meats, oysters and convenience products such as Perdue's grilled chicken.

Not every food processor is convinced it's worth the trouble.

Hormel of Austin, Minn., for example, doubled the life of some of its deli meats to 100 days using high-pressure preservation but sells them only to schools, hospitals and nursing homes, whose concerns about safe meat make them willing to pay higher prices.

A leading Hormel competitor, ConAgra of Omaha, Neb., rejected high pressure for some of its deli meats, concluding that it yielded meat that lacked the texture that spokesman Chris Kircher said consumers demanded. He called it "a little bit of rubberiness."

High pressure has a lot of advantages, however.

First, it offers better protection than chemical additives from food-borne illnesses such as salmonella and listeria, which, according to the federal Centers for Disease Control and Prevention in Atlanta, kill about 5,000 Americans a year. That helped it win U.S. Department of Agriculture approval.

Second, high-pressure preservation eliminates the need for chemical preservatives. In the case of fruit, it also eliminates the need for cooking, which dulls flavors and destroys vitamins and other nutrients. That's what's behind visions of new vending-machine products such as truly zingy fruit smoothies and orchard-fresh orange and apple juice.

A third advantage appeals both to the USDA and to the food industry: High-pressure preservation extends shelf life. This could mean new and expanded markets for U.S. producers.

Take Don Bowden, 72, of Keller, Texas, the president of Avomex Inc., the grand old man of high-pressure entrepreneurship.

Bowden owned a string of Mercado Juarez Tex-Mex restaurants in Dallas and Fort Worth, Texas, in the `80s and made his guacamole at a plant in Sabinas, Mexico. If the guacamole were trucked north into Texas—fast—he could distribute it almost statewide. A better preservative, Bowden thought, could expand his market dramatically.

So he and about 30 pounds of avocado flew to Columbus, Ohio, in 1989 to visit Autoclave Engineering, which made machines that sterilized doctors' implements by pressure-cooking them. The idea of preserving food with water pressure wasn't new; it dated to 1895. What was new was Autoclave Engineering's improved pumps and stronger water tanks.

Working without heat, technicians produced an astronomic pressure of 80,000 pounds per square inch. They also produced avocado pulp that, if vacuum-packed and refrigerated, tasted fresh for 30 days. It's now sold nationwide as AvoClassic guacamole.

So how does Bowden's AvoClassic guacamole taste?

"It tastes like it's fresh," Bowden said. "But then we never had any ugly children in my family, so you'd better ask someone else."

Jimmy Pumarol, the manager of Cafe Atlantico, a fancy nuevo Latino restaurant in Washington, is a good candidate. His servers prepare guacamole tableside from a single ripe Haas avocado. Pounded in a mortar and pestle made of lava, spiced to order and served with warm tortillas, it costs $9 at lunch and $10 at dinner. Even at those rates, Cafe Atlantico goes through about 25 to 30 cases of avocados a week.

Pumarol summoned sous chef Samantha Withall and bartender Marco Guzman, who called for chips and tortillas.

They dug in.

"It's very good! It tastes fresh. It's very flavorful!" said Pumarol, as astonished as a Frenchman encountering a great wine from Ohio. Guzman nodded in agreement.

"Is this AvoClassic?" Withall asked. "It's a great product. My roommate and I buy it at Costco."


To learn more about high-pressure technology, go to Avure Technologies' Web site, at Click on "News" to learn which foods use the new process.

To learn who's selling AvoClassic guacamole near you, go to


(c) 2005, Knight Ridder/Tribune Information Services.

PHOTOS (from KRT Photo Service, 202-383-6099): HIGHPRESSUREFOOD

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