Evaluation of corn oil as an additive in the pre-enrichment step to increase recovery of Salmonella enterica from oregano. (August 2016)

• Record Type: Journal Article
• Authors: Jean-Gilles Beaubrun, Junia; Flamer, Marie-Laure; Addy, Nicole; Ewing, Laura; Gopinath, Gopal; Jarvis, Karen; Grim, Chris; Hanes, Darcy E.
• Is Part Of: Food microbiology. Volume 57(2016:Aug.)
• Page Start: 195
• Page End: 203
• Publication Date: 2016-08
• Subjects: Salmonella spp. -- Montevideo -- Oregano -- Additives -- Corn oil -- Molecular serotyping -- Shot-gun metagenomics; Food Microbiology -- Periodicals; Aliments -- Microbiologie -- Périodiques; Food -- Microbiology; Periodicals; Food -- Microbiology -- Periodicals; Food contamination -- Periodicals; 664.001579
• DOI: 10.1016/j.fm.2016.03.005
• Languages: English
• ISSNs: 0740-0020

Abstract

Abstract: Phenolic compounds associated with essential oils of spices and herbs possess a variety of antioxidant and antimicrobial properties that interfere with Salmonella detection from fresh and dried products. Finding a compound to neutralize the effect of these antimicrobial compounds, while allowing Salmonella growth during pre-enrichment, is a crucial step in both traditional pathogen isolation and molecular detection from these foods. This study evaluated the effectiveness of corn oil as a component of the pre-enrichment broth to counteract antimicrobial compounds properties and increase the recovery of Salmonella from spices. Oregano samples artificially contaminated with Salmonella enterica were pre-enriched in modified Buffered Peptone Water (mBPW) supplemented with and without 2% (vol/vol) corn oil respectively. Samples were incubated overnight at 37 °C. The results showed that recovery of Salmonella from oregano samples was increased by ≥50% when pre-enriched with corn oil. Serovars were confirmed using a PCR serotyping method. In addition, shot-gun metagenomics analyses demonstrated bacterial diversity and the effect of corn oil on the relative prevalence of Salmonella in the oregano samples. Modifying pre-enrichment broths with corn oil improved the detection and isolation of Salmonella from oregano, and may provide an alternative method for pathogen detection in dried food matrices such as spices. Highlights: Evaluation of the effectiveness of corn oil as an additive in pre-enrichment broth. Increased recovery of Salmonella spp. in oregano due to corn oil. Detection of pathogens from oregano using microbiological and metagenomics analyses.