Wednesday, August 24, 2022

Ultra-violet light shows promise for food safety

Trials at Pennsylvania State University indicate that pulsed broad-spectrum light can greatly reduce food-poisoning bacteria that plague the food industry, hospitals, water treatment plants and pharmaceutical production facilities.

The ultra-violet spectrum is particularly effective, the results show.

The approach also destroys bacteria that are resistant to antimicrobials. It's a system that differs from traditional ultra-violet treatments.

“Any improvements to prevent illness or save lives would be the best outcome of this research,” said Ali Demirci, professor of agricultural and biological engineering at Penn State and member of the research team.

“We want to reduce the number of foodborne disease fatalities to zero,” he said.

Over the past two decades, the lab has applied the technique to a range of foods, including fruits, seeds, grains, cheese, milk, apple juice and multiple poultry products. The team even simulated production conditions to test the technology on eggs, using a conveyor devised to test the process in an industrial setting, with the xenon flashlamps designed to operate at commercial scale.

The team said they hope this technology will be adopted by the food industry sooner rather than later due to its strong potential to help make food safer to consume.

Since the 1960s, the food industry has used low intensity ultra-violet (UV) light as an antimicrobial treatment, said Ed Mills, associate professor of meat science.

Meat producers used low levels of UV light in meat-aging facilities, but the technique could only be used at low intensity over a long period of time.

“This is a completely different system,” Mills said. “We are using pulsed light instead of continuous light, which takes advantage of the stored energy in a pulse, so we can deliver more power in less time.”

The team’s technique is designed to be deployed on a food conveyor, where light pulses would be applied to the product as it passes by. 

The treatment delivers a higher intensity of light, because it is pulsed, which results in a greater microbial reduction in a shorter period of time than conventional UV light treatment, Mills said.