Isoeugenol significantly inactivates Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in refrigerated tyndallized pineapple juice with added Yucca schidigera extract

Publication date: Available online 21 June 2019Source: Food ControlAuthor(s): Emalie Thomas-Popo, Aubrey Mendonca, James Dickson, Angela Shaw, Shannon Coleman, Aura Daraba, Armitra Jackson-Davis, Floyd WoodsAbstractThe antimicrobial effectiveness of isoeugenol against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in refrigerated (4 °C) pineapple juice (PJ) with added 0.5% (w/v) yucca extract (YEX) was investigated. Sub-lethal injury of pathogen survivors and sensory characteristics of PJ were also evaluated. Samples of PJ with YEX and isoeugenol at 0 (control), 0.50, 0.75, 1.0, or 1.5 μL mL−1 were each inoculated with a five-strain mixture of one pathogen to obtain an initial viable count of ∼7.1 log CFU mL−1. During storage of PJ at 4 °C for 70 days, numbers of non-injured and sub-lethally injured survivors were determined by plating diluted juice samples on selective and non-selective agar. The minimum inhibitory concentration (MIC) of isoeugenol for E. coli O157:H7 and S. enterica was 0.5 μL mL−1 in brain heart infusion broth and the MIC for L. monocytogenes was 0.2 μL mL−1. The minimum bactericidal concentration (MBC) for E. coli O157:H7 and S. enterica was 0.6 μL mL−1 while the MBC for L. monocytogenes was 0.4 μL mL−1. All three pathogens survived for more than 42 days in the control juice. After 2 h, isoeugenol inflicted sub-lethal injury in pathogen survivors. Isoeugenol at 1.5 μL mL−1 co...
Source: Food Control - Category: Food Science Source Type: research