Assessment of the Hygienic Characteristics of a Beef Carcass Dressing Process

Abstract

Swab samples were obtained from the surfaces of randomly selected beef carcasses passing through a high-speed dressing process. A single sample was obtained from each selected carcass from one of 10 sites. At each of 3 points in the process, 25 samples were obtained from each carcass site. The aerobic bacteria, coliforms, and Escherichia coli recovered from each sample were enumerated. Values for the means and standard deviations of each set of 25 values were calculated on the assumption that each set of values was log-normally distributed. The E. coli data indicated relatively heavy (mean log numbers > 2/100 cm2) contamination of carcasses with E. coli during the skinning of posterior sites; redistribution of E. coli, from relatively heavily to relatively lightly (mean log numbers about 0/100 cm2) contaminated sites during evisceration operations, and reduction of E. coli numbers at most sites as a result of trimming and washing operations. However, posterior sites remained the most heavily contaminated with E. coli. The findings for coliforms were similar to those for E. coli. In contrast, the total count data indicated heavy (mean log numbers > 3/cm2) contamination of anterior (brisket) sites as well as posterior sites and little redistribution of bacteria during evisceration operations. After trimming and washing operations, the mean log total numbers at most sites were about 2/cm2, but one brisket site remained heavily contaminated. It is suggested that E. coli or coliform data are appropriate for assessing carcass dressing processes for hazard analysis critical control point (HACCP) system purposes, while total count data are inappropriate for that purpose but may be appropriate, in relation to product storage stability, for quality management (QM) system purposes.

Effects of Acid Adaptation of Escherichia coli O157:H7 on Efficacy of Acetic Acid Spray Washes To Decontaminate Beef Carcass Tissue

“…In the present work, we have demonstrated that acid adaptation of E. coli O157:H7 can negatively affect the ability of organic acid spray washing to reduce the numbers of this organism from prerigor BCT. Pathogens contaminating freshly slaughtered beef carcasses typically are recent residents of the bovine gastrointestinal tract, arriving in feces or ingesta from intestinal organs that are accidentally damaged during removal from the carcass or from feces or environmental soil from the hide or hooves (2,24). Organic acid spray washes are used in the early steps of beef carcass processing.…”

Use of a Marker Organism To Model the Spread of Central Nervous System Tissue in Cattle and the Abattoir Environment during Commercial Stunning and Carcass Dressing

“…The latter values became Ϫ3.00 on the log scale while no appreciable difference was made to the nonzero values. This allows all data to be reported while in no way biasing the results (10,11). The statistical package used was Genstat 5 (Rothamsted Experimental Station, Harpenden, United Kingdom).…”

Genotypic Analyses of Escherichia coli O157:H7 and O157 Nonmotile Isolates Recovered from Beef Cattle and Carcasses at Processing Plants in the Midwestern States of the United States

“…A few reports have suggested that hides are a significant source of bacterial carcass contamination (6,10,34,44). Most reports have approached the problem by examining the potential for carcass contamination at critical processing steps by following changes in total aerobic, coliform, or generic E. coli counts or some combination of these (6,(17)(18)(19). These measurements can imply causality but lack the ability to directly link sources with the introduction of specific organisms (contamination events).…”