Inhibition of Listeria in cold-smoked salmon using liquid smoke and isoeugenol

Thesis (M.S.) University of Alaska Fairbanks, 2000Listeria monocytogenes is a foodborne pathogen, ubiquitous in nature and sometimes found in seafood. Cold-smoked salmon products have few barriers to inhibit pathogen growth. This study investigated the antilisterial effects of liquid smoke and the phenolic compound isoeugenol. Five commercial liquid smokes were tested 'in vitro' and the most inhibitory to Listeria monocytogenes ATCC 19115 and L. innocua ATCC 33090 was Charsol Supreme. Chum salmon samples (100-g each) were dipped for 15 seconds at varying concentrations of liquid smoke, processed, and analyzed for L. innocua. Liquid smoke concentrations of 60-100% reduced L. innocua by 3-logs in the final product. Dwell times of 15 seconds to 5 minutes using 60% liquid smoke gradually decreased listerial survival. Isoeugenol was antilisterial 'in vitro, ' but lacked synergism with liquid smoke in cold-smoked salmon. Charsol Supreme formed an antilisterial barrier in cold-smoked salmon, and may be a useful application to commercial products