The impact of lamb cleanliness and line speed on the effectiveness of steam vacuum and carcass wash as decontamination methods after slaughter

Abstract

This study assessed the effectiveness of steam vacuum and carcass wash in decontaminating lamb carcasses by measuring Enterobacteriaceae, total viable counts (TVC), and visible contamination. In addition, different levels of fleece cleanliness and different line speeds were evaluated for each group. The sampling covered four groups: i) control, ii) steam vacuum, iii) carcass wash, and iv) steam vacuum and carcass wash.A total of 660 surface swabs were collected: i) before treatment, ii) after treatment, and iii) 24 h post chilling. The results showed that Enterobacteriaceae and TVC means were significantly lower (P < 0.001) on the steam vacuum group compared to the other groups, both after treatment and after chilling. Conversely, the carcass wash was effective in removing visible contamination but not significant on microbial reduction. There was a significant difference (P < 0.001) between line speeds on TVC means, but not on Enterobacteriaceae means. Cat 3 unshorn lambs yielded carcasses with the lowest Enterobacteriaceae means, but with greatest TVC means and wool contamination.