title: Tracing the contamination origin of coliform bacteria in two small food-processing factories.
abstract: The objective of this study was to trace contamination sources of coliform bacteria by comparing the types of coliforms between food samples and the processing environments in two small food-processing factories (factories A and B). Fermentation tests of five sugars enabled the successful classification of 16 representative type strains into eight distinct groups. The grouping procedure was then applied to comparison of the coliform flora between food products and various locations in their processing environments. The consistency between each food and the tested locations was evaluated using the Jaccard index. The air conditioner and refrigeration room floor in factory A showed an index of 1.00, while the shaping machine in factory B showed an index of 0.98, indicating that these locations could be contamination sources. The validity of our results was confirmed by randomly amplified polymorphic DNA, which showed 100% matched profiles between the air conditioner and the food in factory A, and highly matched profiles between the machine and the food in factory B. This method for comparing the coliform flora between food and environments has the potential to be a reliable tracing tool for various food industries.
authors.affiliation: Saitama Industrial Technology Center North Institute, 2-133 Suehiro, Kumagaya-shi, Saitama 360-0031, Japan. tominaga@saitama-itcn.jp
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Tominaga
authors.forename: Masahiro
authors.initials: M
authors.lastname: Sekine
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Oyaizu
mesh_terms: D000389:Air Conditioning / Q000295:instrumentation; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004755:Enterobacteriaceae / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D004783:Environmental Microbiology; D005430:Floors and Floorcoverings; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005525:Food-Processing Industry; D006801:Humans; D019105:Random Amplified Polymorphic DNA Technique
chemical_list: D004269:DNA, Bacterial