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If the same process worked on oysters, it might mean an end to the health concerns about eating the tasty shellfish raw.

Somehow, the literature suggested, treating berries with very high water pressures either killed the microorganisms or inactivated the enzymes involved, and the delicate fruit kept its fresh flavor and texture significantly longer.

Purifying oysters without altering their taste or texture; any such process was certainly worth a try. Oysters are a large part of the Voisin family business. Son Mike runs Motivatit Seafoods, and Ernie, a retired engineer, takes intense interest in the business, a business very sensitive to health concerns.

The Vibrio vulnificus bacteria, for example, has caused problems for the Gulf oystermen in recent years, because it can be deadly for people whose immune systems are already weakened by other illnesses. The threat has brought federal rules requiring warning signs where oysters are served raw. The negative publicity affects sales.

The Voisins were interested in any affordable process that could eliminate the vibrio threat without affecting the oysters' taste and texture. They sought out a local pipe testing company for assistance.

"They normally cap both ends of a joint pipe," Mike said, "and run the pressure up to look for leaks. We used just the caps, put in a few oysters and pressurized it to about 10,000 psi, the maximum for that system."

They took the treated oysters to Professor Marilyn B. Kilgen, head of the Department of Biological Sciences at Nicholls State University, for testing.

The results were disappointing. Either the test pressures were not high enough, or Vibrio and other microorganisms found naturally in oysters, were not susceptible to pressure treatment.

"When 10,000 pounds was not enough," Mike recalls, "we went to the Illinois Institute of Technology in Chicago."

Labs there had equipment capable of much higher pressures. "Our goal was to keep the oyster alive and kill the bacteria," Mike said, and this time, at 50,000 psi, the process worked. The laboratory counts for all the bacteria were greatly reduced, and the pesky vibrio vulnificus was among those that couldn't take the pressure.

But there appeared to be a critical problem. The oysters had been processed whole, alive, in the shell, just the way they were marketed to oyster bars. A living, healthy oyster keeps its shell tightly shut when it is out of the water.

The oysters that had been processed at 50,000 psi all showed telltale gaps where there should have been tight natural seals. Using the traditional criteria for the oyster freshness, pressurization had failed. No matter how pure the oysters, who would buy them if they "looked" dead?

But the "problem" soon turned out to be a remarkable bit of luck. Kilgen determined that the oysters gapped open because the pressure had affected the natural "glue" that attached the mollusk's closing muscles to the shell.

Those muscles, which ordinarily must be cut free by a human oyster "shucker," simply came "unglued" allowing the shells to be separated without effort, to reveal perfect oysters that may be lifted from the shell with only a spoon.

And when the processed oysters passed all the taste and texture tests, the Voisins knew they had stumbled upon an innovation that could end the industry's reliance on old-time oyster shuckers. And just in time.

"There are not that many oyster shuckers left," Mike explained. "And there are nearly no new entries into the tedious, low paying job classification. We have shuckers here, but finding someone who can shuck oysters for a bar in Kansas City is nearly impossible."

The pressure processed oyster could change all of that and make it possible for a waitress to "open," and serve a dozen perfect raw oysters without even getting her hands wet.

The Voisins immediately applied for patents to protect three separate elements of their new process, the design, the "shucking," and the reduction of bacteria that originally led them to investigate pressure treatment. They are developing the equipment that will enable them to pressure process oysters on a commercial scale.

"We will sort and clean the oysters just as before," Ernie Voisin said. "Then we will put a gold-colored plastic band around each raw oyster before loading them by batches into the pressure processor."

The shrink-wrap band will hold the oyster tightly shut, substituting for the creature's muscle, and holding the natural juices inside.

"And when a shipment of 'gold-banded' Motivatit oysters arrives in Kansas City,"Mike said, "the waitress can clip the bands and serve the oysters as easily as she can prepare a salad."

"We've been working on this for about a year and a half," he said. "My father is something of a mechanical genius, and he is working with engineers to build the processing equipment that can handle commercial quantities of oysters at those high pressures."

They expect to have the process running in time for a June meeting of the Interstate Shellfish Sanitation Conference.

-Bill Ellzey