Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SATURDAY, July 23, 1994 TAG: 9407250011
SECTION: CURRENT PAGE: NRV-1 EDITION: NEW RIVER VALLEY
SOURCE: ALLISON BLAKE STAFF WRITER
DATELINE: BLACKSBURG LENGTH: Medium
With it, they expect to finally discover "an exact known defect dimension" in food-product packaging.
In other words, they're going to figure out how big a hole your yogurt cup can bear before bad bacteria slip in.
Believe it or not, nobody knows for sure, say the researchers.
It's not that the yogurt and bologna you eat now are improperly packaged. ("You have the safest food system in the history of man," said Joe Marcy, an associate professor at Tech's Department of Food Science and Technology.)
But now, the food industry spends millions doing what it calls "destructive testing" - banging, tapping and otherwise shaking up packaged foods to see if and when the flaws in packaging appear.
If Marcy, graduate student Scott Keller, and adjunct professor Barbara Blakistone succeed, they'll be able to provide the standard that will allow the food industry to test plastic packaging.
The research has been paid for by a mix of state funds, but Ross Laboratories in Columbus, Ohio, recently added $10,000, Marcy said. Months will pass before the final results are known.
But Keller is putting in some serious time to move the study ahead. Just this past weekend, he hooked a brew of bacteria to an aerosol tank, stood in front of the equivalent of an aquarium, and aimed carefully timed squirts at the plastic baggies inside. The seal on each baggie had been pierced by the microtube, which is 10 microns in diameter, explained Blakistone.
The little buggers in the brew are called pseudomonas, little one-micron critters that commonly show up in crops.
"I'm using it because they're small" and mobile, said Keller.
And therein lies a key to his research, said Keller. It seems logical that a safe hole in food packaging would be the same size as the smallest threat - but it's not. All sorts of forces come to bear on a bacterium's movement, aiding and abetting the microbe's charge.
One must consider the thickness of the plastic wrapping the cheddar, or whether tomato juice has oozed through the can to help conduct the bad guys inside.
Until the Tech researchers got hold of these tiny microtubes, nothing small enough existed to poke holes in plastic packaging.
The tubes were invented by Phillips Laboratory at California's Edwards Air Force Base, and efforts are under way to sell them for all sorts of uses, said researcher Wesley Hoffman.
They have a tons of potential: They may improve the resolution of CAT-scan images, help shrink the size of computers, and create more dense insulation, said Hoffman.
And they're going to make an already safe food system even safer.
Keller's professor, Marcy, tapped a plastic container of chocolate pudding, sealed with thin plastic. It's possible that seal will be better checked in the future, thanks to the current Tech project.
It's a safeguard companies probably are willing to buy, said Marcy. Everyone who remembers the Tylenol contamination scare can imagine "what would happen tomorrow if Dan Rather came on" the news to announce deaths from chocolate pudding, he said.
by CNB