title: Spoilage characteristics of Brochothrix thermosphacta and campestris in chilled vacuum packaged lamb, and their detection and identification by real time PCR.
abstract: The spoilage potential of Brochothrix campestris and Brochothrix thermosphacta was investigated in vacuum-packed lamb. Striploins (n=338) were inoculated and stored for twelve weeks at temperatures -1.5, 0, 2 and 7 °C. Growth around 5-6 log10 CFU/cm(2) was recorded after six weeks at 0, 2 and 7 °C, and ~3 log10 CFU/cm(2) after nine weeks at -1.5 °C. B. campestris was shown to cause spoilage by nine weeks at temperatures above 0 °C by the presence of green drip and unacceptable odours. Molecular based assays for the detection and differentiation of B. thermosphacta and B. campestris were developed and validated. A TaqMan assay was designed to target a unique single-nucleotide polymorphism in the Brochothrix 16s rRNA gene with a sensitivity of <7 CFU per reaction. Secondly a specific PCR was designed for B. campestris targeting the structural genes, brcA and brcB. These testing regimes offer a rapid and cost effective method for the detection and screening of Brochothrix species in meat products and processing environments.
authors.affiliation: Food Assurance and Meat Quality, AgResearch Ltd, Hopkirk Research Institute, Cnr University Ave and Library Road, Massey University, Palmerston North 4442, New Zealand.
authors.forename: Amanda
authors.initials: A
authors.lastname: Gribble
authors.forename: Gale
authors.initials: G
authors.lastname: Brightwell
mesh_terms: D000818:Animals; D058640:Brochothrix / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D018857:Food Packaging; D008461:Meat Products / Q000032:analysis / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D034561:Sheep, Domestic / Q000382:microbiology*; D014618:Vacuum
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S