The Microbiological Status of Condensation in Carcase Chillers

Summary

Condensation in carcase chillers is a continuing problem in many abattoirs, both export and domestic registered.

Often engineering solutions are difficult and expensive to implement and condensation can only be controlled by manual mopping.

An evaluation of the microbiological status of condensation on both clean and dirty chiller surfaces and steel work was undertaken to assess the bacterial load.

Over a five month period, five abattoirs, in South-East Queensland and Northern New South Wales, were visited by Australian Meat Technology staff. Three were export registered and two were domestic plants.

The chillers were visually assessed and samples of condensation were collected for microbiological assessment. Heavily soiled evaporators were cleaned in one plant to determine the effect of cleaning on the microbial status of both the evaporators and the chiller air.

The amount of condensation present in the chillers varied greatly. In some instances large volumes were able to be collected, whereas, in other cases it was not possible to collect enough sample to accurately undertake analysis.

Where chillers were kept in a clean and hygienic manner there was no evidence of the presence of coliforms or E. coli in the condensation. However, for some chillers which were in need of maintenance cleaning, the condensation collected was contaminated with coliforms.

Manual cleaning of evaporators and fins reduced the bacterial load present although it appeared to have little effect on the overall level of airborne bacteria during limited monitoring.

Due to the limited scope of this project the long term effect of cleaning evaporators on the airborne bacterial load, could not be assessed.