A measure of freshness

Just in time for Thanksgiving, a Lexington company is marketing the perfect gift for the paranoid chef who has everything: a pocket-sized device that detects spoiled meat.

Food Quality Sensor International Inc. of Lexington (FQSI) makes the SensorfreshQ, a hand-held scanner that can detect high bacteria levels on meat and poultry. The $90 device, which went on sale recently at specialty retailer The Sharper Image, uses sensor technology developed at Draper Laboratory in Cambridge to identify spoiled meat, even if it still looks and smells fresh.

Most of Massachusetts' top technology firms make products for business and government -- massive data storage arrays from EMC Corp., guided missiles from Raytheon Co., or cellphone chips from Analog Devices Inc. There are a few exceptions, like Bose Corp. and iRobot Corp. Now FSQI hopes join their ranks by selling millions of its SensorfreshQs.

"There are all kinds of ways that foods can spoil . . . and this device is a handy way to detect that spoilage," said FQSI president Marco Bonne, a food industry veteran who served as president of Prince Foods in the 1980s.

As bacteria feast on the protein in meat, they generate tiny amounts of chemicals called biogenic amines. These chemicals mix with the surrounding air, but people can't smell them. Megan Owens, founder of FQSI, developed an amine detection system while working at Draper Lab . Owens designed an array of tiny sensors that generate an electrical current in the presence of biogenic amines. At the touch of a button, a tiny fan inside the device growls to life, blowing an air sample over the sensors. In about a minute, the machine delivers its reading through a set of colored lights. Green means the meat is fresh; yellow means you'd be wise to eat it within 48 hours; and red indicates a trip to the wastebasket.

After about 200 uses, the sensor array must be replaced. They snap out of the unit easily, and replacement sensors sell for $9.95 a pair. The scanner works on protein foods like meat and poultry, but not vegetables, like the tainted spinach that sickened hundreds of people nationwide earlier this year.

Bonne said he thinks the SensorfreshQ will find a ready market among health-conscious Americans. About 76 million Americans acquire a food-borne illness every year, and 5,000 die from them, according to the Centers for Disease Control and Prevention.

But Mark Kantor , associate professor in the department of nutrition and food science at the University of Maryland, was unimpressed by the SensorfreshQ . Although he hasn't tested the technology, Kantor said it's a complex, costly solution to a simple problem. He said consumers could simply check the sell-by date on meat packages before buying it, and discard meat that smells bad or has a slimy texture. Kantor also said that some of the most dangerous microorganisms might not emit enough amines to set off an alarm.

"It's possible that meat could be full of E. coli or salmonella or other bacteria that could really make you sick, and this device wouldn't detect anything," he said.

Bonne said that the SensorfreshQ does not specifically detect deadly pathogens like E. coli or salmonella, although the device will pick them up if the concentration is high enough.

"We are not testing for pathogens," said Bonne. "We are testing for freshness."

The handheld meat scanner is just an opening gambit for FQSI. The company hopes a successful launch of the scanner will encourage the nation's meatpackers to place its spoilage sensors directly inside millions of packages of meat. As amines seep from spoiled meat, the sticker changes color to alert grocers and consumers.

Hiawatha Bray can be reached at bray@globe.com.