Possibility of Campylobacter jejuni inactivation in smoked salmon by high-pressure treatment

Abstract

The sterile samples of cold-smoked salmon were placed in polyamide–polyethylene pouches and inoculated with three-strain composite of Campylobacter jejuni (inoculum ca 10⁷ CFU g⁻¹). The inoculated samples were sealed under vacuum and subjected to 200, 300 and 400 MPa of hydrostatic pressure for 0, 5, 10 and 15 min. The number of surviving C. jejuni per gram was determined by the 10-fold dilution method followed by plating on Karmali agar. D ₁₀ values were calculated. This work has shown that for reducing C. jejuni in cold-smoked salmon by 6 log units, the application of 200 MPa for 64.26 min or 300 MPa for 17.10 min or 400 MPa for less than 5 min is needed. Applying such parameters of high-pressure processing should not change significantly the organoleptic properties of the product.

Keywords:

• high-pressure processing
• Campylobacter jejuni
• smoked salmon
• microbial inactivation
• organoleptic properties

Acknowledgements

This work was partially supported by a grant No 2 P06T 006 29 2005–2008 from the State Committee for Scientific Research, Ministry of Education and Science, Poland.