Bacteria are good for controlling germs

The US Department of Agriculture (ARS) has invented a new way to treat food safety that can increase the effectiveness of traditional food safety methods.

ARS microbiologist Ching-Hsing Liao invented and tested a method to bring beneficial bacteria against harmful latent bacteria. Beneficial bacteria inhibit the growth of pathogens that exist in early chemical and physical pathogens. Pathogens are the main source of foodborne illness in the United States.

At ARS's Eastern Research Center (ERRC) in Wyndmoor, Pa., Liao has identified three beneficial antagonistic bacteria used in food safety interventions. He soaked ornamental peppers in aqueous solution containing beneficial antagonistic bacteria and examined the effects of external pathogens such as Salmonella and E. coli O157: H7.

A strain of bacteria called Pseudomonas fluorescens 2-79 is useful. When soaking bell peppers in solution containing bacteria Pf 2-79 for about 2 minutes, the pathogen multiplication is almost completely inhibited.

ARS researchers have identified three beneficial bacteria in controlling the development of pathogens in fresh fruits and vegetables.These bacteria are tested by soaking bell peppers in solutions containing beneficial bacteria.(Photo: USDA)

In untreated bell peppers, the number of pathogens multiplies about 100,000 times at a temperature of 68 degrees F for a 2-day storage period. But the treated peppers with bacteria Pf 2-79 inhibit the growth of pathogens. This treatment can potentially prevent pathogens from multiplying so much that it can cause illness in humans.

Immersion in this beneficial microbial solution also prevents the growth of two bacteria that cause food spoilage and reduces the rapid increase in rot diseases.

Pf 2-79 bacteria are easy to grow and can settle in some foods. Because it can live in air-conditioned temperatures, it can be an effective control agent for cold-tolerant pathogens such as Listeria monocytogenes and Yersinia enterocolitica.

Liao and his colleagues plan to validate their research on a large scale. Their research also aims to identify sub-bacterial strains that can be used with Pf 2-79 to improve the quality and safety of food more.

Consumers can contribute to pushing pathogens away from home products by implementing simple food safety precautions such as peeling, rinsing and cooking.