Investigation ofvacuuming equipment for removal of wool and fleece dust contamination from sheep carcases

Summary

In early 1997, AQIS approved the use of vacuuming treatments involving steam or hot water to remove faecal and ingesta contamination from carcases with the provision that areas of contamination of 25mm or greater in the greatest dimension must continue to be removed by trimming.

In August 1997, AQIS advised its technical staff that the equipment was not yet approved in Australian export establishments for use on sheep or lamb carcases to remove wool fibres and fleece dust by sweeping.

At the request of the Meat Research Corporation, investigations were undertaken to facilitate consideration of an approval of the equipment for this purpose for treating sheep and lambs. The investigation assessed two issues:

the ability of the vacuuming unit to remove individual fibres and clusters of wool and wool dust
whether the method of sweeping the unit head across the surface of the carcases is acceptable
The vacuuming unit was evaluated at an export establishment. The evaluation involved both visual and microbiological assessments of mutton carcases.

Visual assessments of carcases were undertaken to determine the initial level of visual wool and dust contamination and then to determine if the unit was able to remove visible contamination.

Microbiological analysis of the carcases was undertaken to determine if the unit was able to reduce the bacterial load in contaminated surfaces.

The unit was found to be capable removing wool and wool dust from the surface of sheep carcases. Microbiological counts on carcases after treatment were less than before treatment and there was no evidence to suggest that the sweeping motion relocates contamination.