The university's new Interferometric Biosensor is one of the latest in a series targeted at the food industry. The interferometric tackles thepoultry industry's pursuit of better methods for controlling foodborne pathogens in the plant.
Over the last decade the poultry industry has implemented the systematic microbial screening of products and processes. Most processing operations have also introduced new rinse and anti-microbialtreatments.
"Yet, the long time delay between sample collection and obtaining microbial screening results continues to hamper the efficiency of these programmes," Georgia Tech said in anannouncement about the new biosensor.
"In the absence of simple, inexpensive, and rapid microbial detection techniques, little feedback is available to help plants recognise changing microbialconditions as they are occurring. This, in turn, prevents them from better managing the intervention resources they are using to control microbial contaminants."
Laboratory tests indicate the new Interferometric can detect the presence of salmonella and campylobacter in less than 30 minutes.
"More importantly, the sensor has been designed not only to be inexpensive and portable, but also to be used within a processing plant environment to provide feedback to help controloperating performance," the university said.
The Interferometric Biosensor's key elements are a laser diode, a waveguide and an image detector. As molecules or microbes bind to capture antibodies on the waveguide surface, they alter thepropagation speed of light within the waveguide. Changes in that wave interference pattern allow the sensor to measure the amount of pathogens present in a sample, Georgia Tech says.
Biosensors, a $7.3bn market in 2003, are electronic devices capable of measuring the presence, identity and quantity of an organism. Biosensors commonly use antibodies and nucleic acids to detect theorganisms. They are commonly used in the medical, environmental and pharmalogical sectors but in recent years their use has been extended to the food and beverage industry to pick up harmful pathogensand decay in products.
The unique ability of antibodies to bind only one specific molecule or microbial species within a sample make the devices one of the most popular rapid screening techniques in use today, Georgia Tech says.
While biosensors have been around since the 1970s, they have only recently begun to appear commercially for use in food processing. The majority of commercial biosensors are are targeted at laboratory-based testing operations.
Other sensors developed for the food industry include Canary, designed by researchers at the Massachusetts Institute of Technology. Canary can detect E. coli O157:H7 on lettuce within five minutes under laboratory testing conditions. Michigan State University's Electrochemical Biosensor is a disposable device that can detect E. coli O157:H7 andSalmonella in fresh produce and meat products within 10 minutes.
Penn State's Magnetoelastic Sensor resonates in response to an externally applied magnetic field impulse and can detect small amounts of E. coli O157:H7.
"What may ultimately separate these sensors, however, down the road could be their ability to be used in remote settings, such as on-line in a processing plant, and to be operatedautomatically as part of a feedback mechanism for process control," Georgia Tech stated. "Here simplicity of operation and ruggedness will play increasingly important roles as will systemand operating costs."