Effect of moderate intensity pulsed electric field on shelf-life of chicken breast meat

1. Moderate intensity pulsed electric field (MIPEF) is a fairly new research topic for microbial inactivation on muscle foods. In this study, indirect application of MIPEF (2.5 kV/cm, 4.67 kV/cm, 7 kV/cm) was evaluated in terms of the growth of some pathogenic bacteria and the quality characteristics of chicken breast meat during cold storage (4 degrees C). 2. This study was conducted in two stages. In the first stage, pure cultures of S. enteritidis, P. aeruginosa, S. aureus, L. monocytogenes, E. coli and C. jejuni were inoculated in broth and stored in a refrigerator at 4 degrees C under MIPEF. Both E. coli and C. jejuni showed a remarkable resistance to MIPEF under 4.67 kV/cm and 7 kV/cm, respectively. 3. In the second stage, MIPEF was applied to packaged chicken breast samples. The limit for total mesophilic aerobic bacteria (TMAB) count was exceeded in 4.67 and 7 kV/cm applied groups 2 d later than seen in the control group (C). Almost 2 log differences were determined for total coliform bacteria in 4.67 and 7 kV/cm applied groups as compared to C (P < 0.05). Inoculated P. aeruginosa count remained the same, whereas L. monocytogenes growth was promoted by 4.67 kV/cm (P < 0.05). 4. pH value, CIE L*, b*, C* colour values of chicken breast fillets were not affected by MIPEF application while Delta E values showed the maximum change in the C group. 5. This study demonstrated that improved shelf-life of chicken breast fillets was provided by moderate intensity DC-pulses in combination with cold storage.