Inactivation of pathogenic Escherichia coli in ground chicken meat affected by high-pressure, process time, temperature, allyl isothiocyanate, and acetic acid

Authors: Sheen, Shiowshuh - Allen

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Shiga toxin-producing Escherichia coli (STEC) O157:H7 is one of the most prevalent foodborne pathogens associated with meat outbreaks in the United States. High-pressure processing (HPP) may be applied to inactivate microorganisms with the addition of allyl isothiocyanate (AITC) and acetic acid (AA). However, individual, and/or combined effects of HPP, AITC, and AA on the inactivation of foodborne pathogens needs to be established for industry applications and risk assessment. This study was to evaluate the HPP (including operation pressure, temperature, and holding time), AITC, and AA doses (w/w) for their impact, with modeling, on the decontamination of pathogenic E. coli in ground chicken meat. Fresh irradiated ground chicken meat was aseptically mixed with a selected concentration of AITC (0.05-0.2%, w/w) and/or AA (0-0.3%, w/w), inoculated with E. coli cocktail to about 7.0-8.0 log CFU/g initial populations, and subjected to 250-350 MPa high pressure treatment for 10-25 min at -15°C to 4°C. The populations of E. coli before and after treatments were enumerated to determine the pathogen reductions (log CFU/g). A dimensionless non-linear 5-parameter model can be developed to predict the inactivation. AITC and AA alone with concentrations of 0.05–0.20% and 0.0-0.3% (w/w), respectively, were found not significant (p > 0.05) in reducing E. coli populations (<0.5 log CFU/g). The reductions of E. coli resulting from HPP treatment alone were 0.9 (250MPa), 1.5 (300MPa), and 2.0 log CFU/g (350MPa) at 15min and had a significant (p < 0.05) dependence on pressure level. Moreover, there was a significant (p < 0.05) synergy of the combined HPP/AITC/AA treatment with the reductions of E. coli ranging from 1.5 to 7.0 log CFU/g in ground chicken meat. A dimensionless non-linear model was developed and verified to describe the effect of HPP (pressure (MPa), process time (t) and temperature (T)) with two natural antimicrobial compounds on the reductions of E. coli in ground chicken meat – a model of five parameters. The application of HPP/AITC/AA was effective in reducing pathogenic E. coli in ground chicken meat. The identified parameters and developed model may be used for process optimization and risk assessment to enhance the microbial food safety.