In the study, published in the current issue of the Journal of Food Protection, whole-muscle and broken ready-to-eat products (RTE) were inoculated with a five-strain mixture of Listeria monocytogenes.

The research, conducted by a major supplier of the cleaning agent, is a bid to provide assurance to manufacturers that the product will not harm their brands.

The octanoic treatments were applied to the surface of the products by dispensing a specific volume of solution directly into the final package prior to vacuum sealing.

Once sealed, the vacuum-packaged RTE products containing the acid were immersed in water heated to 93.3°C (200°F) for two seconds to effect adequate film shrinkage.

The scientists also evaluated extending the time at which the packaged, treated RTE products were exposed to water heated to 93.3°C using a commercial cascading shrink tunnel fitted with a modified drip pan.

Once treated, the RTE products were examined for survivor populations of L. monocytogenes after 24 hours of storage at 5°C.

The study found that the octanoic treatment of RTE products reduced L. monocytogenes numbers below the maximum allowed levels under current food safety practices, the scientists said.

The products included oil-browned turkey and cured ham.

"The antilisterial activity of octanoic acid was improved by increasing the duration of the heat shrink exposure," they stated in their paper.

The sensory evaluation was conducted with a 60-member trained panel on 11 uninoculated, treated RTE products.

"(The) results from the sensory evaluation demonstrated that 10 of the 11 treated RTE products were not perceived as different (P = 0.05) from the untreated controls," the scientists stated.

Panelists also detected reduced smoke flavour intensity with treated mesquite turkey, although the product was viewed as acceptable.

All of the six scientists conducting the research are affiliated with Ecolab's research centre in Minnesota, US.

Ecolab is a major producers of octanoic acid treatments for the food industry. The treatments are approved wordwide for use as a processing aid in water in various formulations. It can be used as an antimicrobial treatment on red meat and poultry carcasses and fresh fruits and vegetables.

Last year the European Food Safety Authority approved a form of the cleaning acid for use on meat products.