Control foodborne pathogens during processing with low-dose e-beams.

The increasing numbers of illnesses associated with foodborne pathogens has renewed concerns about product safety. Accordingly, the need for optimizing the control of foodborne pathogens has been paramount.

Strategies for the control of these pathogens include interventions applied to animal carcass surfaces as well as post-slaughter interventions. Relatively new treatments for the decontamination of carcasses include the use of acidified sodium chlorite, peroxyacetic acid, cetylpyridinium chloride and activated lactoferrin.

An alternative approach currently being investigated involves applying low-dose, low-penetration electron beam irradiation to chilled beef carcasses prior to fabrication. Research in this area assessed the efficacy of electron beam irradiation to reduce levels of E. coli O157:H7 on a large beef surface. Scientists also evaluated the effect of the treatment on the sensory properties of the product.

A 1 kGy dose of irradiation reduced levels of E. coli O157:H7, inoculated onto sections of cutaneous trunci, by at least 4 logs. None of the flank steak's sensory attributes were affected by any penetration treatment. So it appears that low-dose, low-penetration electron beam irradiation has potential for use as an antimicrobial intervention on beef carcasses during processing. It minimally impacts the organoleptic qualities of the treated beef products.

Antimicrobials applied to ready-to-eat (RTE) meat products include acetates, diacetates, lactates, glucono-delta-lactone, essential oils, nisin, acidic calcium sulfate with propionic and lactic acid, or combinations of these food-grade chemicals. Alternatively, post-lethality treatments, such as hot water, steam pasteurization and high hydrostatic pressure, are being applied before or after a product is packaged. The use of biopreservatives of lactic acid bacteria and bacteriophages are additional approaches that guard against pathogens on RTE products.

While heat is the most common method in use today for inactivating microorganisms, nonthermal physical treatments, such as high hydrostatic pressure, ultrasound, pulsed electric fields and light pulses, can also be used. Both conventional and new treatments can be applied in combination for controlling foodborne pathogens and enhancing the safety and shelf life of foods.

Further information. Vijay K Juneja, Microbial Food Safety Research Unit, USDA-ARS Eastern Regional Research Center, Room 2129.3, 600 E. Mermaid Lane, Wyndmoor, PA 19038; phone: [phone]; fax: [phone]; email: [e-mail].