A study of bacteria contaminating refrigerated cooked chicken; their spoilage potential and possible origin

Cooked chicken was allowed to spoil in a normal kitchen refrigerator (variable temperature) and at a standard 4C. After 10 days' storage, bacteria were isolated from the chicken. It was found that the numbers of organisms at variable refrigeration temperature were tenfold higher than those at a uniform 4C. In an attempt to find the sources of contamination, swabs were made of different areas of the kitchen. Many of the bacteria isolated from the spoiled chicken, were also isolated from the kitchen environment. When pure cultures of organisms isolated from spoiled chicken were inoculated into sterile cooked chicken and held at 4C, the main spoilage organisms were found to be Pseudomonas putida and Aeromonas hydrophila, which were also isolated from the refrigerator where the chickens were stored in the kitchen. Aeromonas hydrophila was found in significantly high numbers on plates, cutting knives, chopping boards and cold water taps.