title: Effect of oxygen stress on growth and survival of Clostridium perfringens, Campylobacter jejuni, and Listeria monocytogenes under different storage conditions.
abstract: This study investigated the growth and survival of three foodborne pathogens (Clostridium perfringens, Campylobacter jejuni, and Listeria monocytogenes) in beef (7% fat) and nutrient broth under different oxygen levels. Samples were tested under anoxic (<0.5%), microoxic (6 to 8%), and oxic (20%) conditions during storage at 7 °C for 14 days and at 22 °C for 5 days. Two initial inoculum concentrations were used (1 and 2 log CFU per g of beef or per ml of broth). The results show that C. perfringens could grow in beef at 22 °C, with an increase of approximately 5 log under anoxic conditions and a 1-log increase under microoxic conditions. However, C. perfringens could not survive in beef held at 7 °C under microoxic and oxic storage conditions after 14 days. In an anoxic environment, C. perfringens survived in beef samples held at 7 °C, with a 1-log reduction. A cell decline was observed at 2 log under these conditions, with no surviving cells at the 1-log level. However, the results show that C. jejuni under microoxic conditions survived with declining cell numbers. Significant increases in L. monocytogenes (5 to 7 log) were observed in beef held at 22 °C for 5 days, with the lowest levels recovered under anoxic conditions. L. monocytogenes in refrigerated storage increased by a factor of 2 to 4 log. It showed the greatest growth under oxic conditions, with significant growth under anoxic conditions. These findings can be used to enhance food safety in vacuum-packed and modified atmosphere-packaged food products.
authors.affiliation: Department of Nutrition and Food Technology, Faculty of Agriculture, The University of Jordan, Amman 11942, Jordan.
authors.forename: Hamzah
authors.initials: H
authors.lastname: Al-Qadiri
authors.affiliation: Department of Biological Systems Engineering, Washington State University, Pullman, Washington 99164, USA. ssablani@wsu.edu.
authors.forename: Shyam S
authors.initials: SS
authors.lastname: Sablani
authors.affiliation: School of Food Science, Washington State University, Pullman, Washington 99164, USA.
authors.forename: Mahmoudreza
authors.initials: M
authors.lastname: Ovissipour
authors.affiliation: Water, Energy and Environment Center, The University of Jordan, Amman 11942, Jordan.
authors.forename: Nivin
authors.initials: N
authors.lastname: Al-Alami
authors.affiliation: Department of Biological Systems Engineering, Washington State University, Pullman, Washington 99164, USA.
authors.forename: Byju
authors.initials: B
authors.lastname: Govindan
authors.affiliation: School of Food Science, Washington State University, Pullman, Washington 99164, USA.
authors.forename: Barbara
authors.initials: B
authors.lastname: Rasco
mesh_terms: D000818:Animals; D016123:Campylobacter jejuni / Q000254:growth & development / Q000302:isolation & purification*; D002417:Cattle; D003016:Clostridium perfringens / Q000254:growth & development / Q000302:isolation & purification*; D003080:Cold Temperature; D015169:Colony Count, Microbial; D003470:Culture Media; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D018857:Food Packaging; D059022:Food Safety; D061353:Food Storage; D008089:Listeria monocytogenes / Q000254:growth & development / Q000302:isolation & purification*; D010100:Oxygen / Q000494:pharmacology*; D000069466:Red Meat / Q000382:microbiology; D013312:Stress, Physiological; D014618:Vacuum
chemical_list: D003470:Culture Media; D010100:Oxygen