title: Survival of spoilage bacteria subjected to sequential eugenol and temperature treatments.
abstract: Effects of a sequential application of eugenol and temperature on the survival of two model spoilage organisms, Staphylococcus carnosus LTH1502 and Escherichia coli K12 C600, were studied. To assess effects of a "temperature first-antimicrobial later" treatment, cultures were treated with eugenol at 20, 37 and 42 °C at the beginning of the incubation period, and after 3h and 8h. To assess effects of an "antimicrobial first-temperature later" treatment, eugenol was added at the beginning of the incubation period at 37 °C and temperature was changed to 20 or 42 °C after 3 or 8h. Cell numbers were determined in regular intervals during the incubation period using plate counts. Partitioning of eugenol was measured by HPLC, and cell morphology was assessed by electron microscopy. Combined treatments were more effective against the Gram negative E. coli than against S. carnosus. Order of application influenced the effectiveness of treatments, especially at 42 °C. There, the temperature first-eugenol later treatment was less effective than other treatments, likely due to temperature-induced adaptation processes occurring in cellular membranes making them more resistant against a later eugenol treatment. Results are of significance in situations where combinations of sublethal stresses are used to build a hurdle concept for food preservation.
authors.affiliation: Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany.
authors.forename: Yudith
authors.initials: Y
authors.lastname: Manrique
authors.affiliation: Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany.
authors.forename: Sarisa
authors.initials: S
authors.lastname: Suriyarak
authors.affiliation: Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Gibis
authors.affiliation: Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Schmidt
authors.affiliation: Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany. Electronic address: j.weiss@uni-hohenheim.de.
authors.forename: Jochen
authors.initials: J
authors.lastname: Weiss
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D015169:Colony Count, Microbial; D024881:Drug Resistance, Bacterial / Q000502:physiology; D048168:Escherichia coli K12 / Q000187:drug effects* / Q000254:growth & development; D005054:Eugenol / Q000494:pharmacology*; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D006358:Hot Temperature; D008826:Microbial Sensitivity Tests; D013210:Staphylococcus / Q000187:drug effects* / Q000254:growth & development; D013312:Stress, Physiological
chemical_list: D000890:Anti-Infective Agents; D005054:Eugenol
keywords: Antimicrobial; Eugenol; Resistance; Sequential; Stress; Survival; Temperature