Biss M E, Hathaway S C
Regulatory Authority, New Zealand Ministry of Agriculture (Meat and Seafood), Te Puke, New Zealand.
J Appl Bacteriol. 1996 Dec;81(6):594-600. doi: 10.1111/j.1365-2672.1996.tb03552.x.
The microbiological contamination of ovine hind legs at sites which were visibly clean (control carcasses), sites immediately adjacent to and below visually contaminated sites, and sites contaminated with visible faecal material or wool were determined by excision sampling immediately after pelting and immediately after a pre-evisceration wash. The mean aerobic plate count (APC) and Escherichia coli count (EC) at clean sites immediately after pelting ranged from log10 cm-2 3.98 to 4.44 and log10 cm-2 0.96 to 1.51, respectively. These levels of contamination were significantly lower than those on sites contaminated with faecal material (log10 cm-2 6.00 and 3.00, respectively) or wool (log10 cm-2 5.44 and 2.45, respectively). The presence of faecal material or wool on the carcass was not associated with increased bacterial numbers on visually clean areas of the carcass. This indicates that the presence of faecal material or wool alone cannot be used as an indicator of the hygienic status of the carcass as a whole, particularly in the role of on-line monitoring parameters for HACCP systems. Pre-evisceration washing of carcasses had very little effect on the uncontaminated areas of the carcasses, but reduced the mean APC and EC at the site of visible contaminants. There was little evidence of redistribution of bacteria to immediately adjacent but visually clean sites. However, the residual levels of both APCs and ECs directly at sites of faecal contamination after washing were still significantly higher than at visually clean sites. Application of HACCP principles to ovine slaughter and dressing suggests that visible faecal material should be removed by trimming, whereas pre-evisceration washes can have a practical and microbiologically validated role in the removal of wool. There was generally a good correlation between APCs and ECs at the uncontaminated sites prior to pre-evisceration washing, suggesting that in some situations APCs can act as a useful indicator of both general carcass hygiene and the presence of faecal indicators.
在屠宰后立即进行剥皮以及预剖腹清洗后，通过切除取样法测定了绵羊后腿在外观清洁部位（对照胴体）、紧邻并低于外观受污染部位的部位以及被可见粪便或羊毛污染部位的微生物污染情况。剥皮后立即检测发现，清洁部位的平均需氧平板计数（APC）和大肠杆菌计数（EC）分别在log10 cm-2 3.98至4.44以及log10 cm-2 0.96至1.51之间。这些污染水平显著低于被粪便污染部位（分别为log10 cm-2 6.00和3.00）或羊毛污染部位（分别为log10 cm-2 5.44和2.45）。胴体上存在粪便或羊毛与胴体外观清洁区域细菌数量增加无关。这表明，仅粪便或羊毛的存在不能用作整个胴体卫生状况的指标，特别是在HACCP系统在线监测参数方面。胴体的预剖腹清洗对胴体未受污染区域影响很小，但降低了可见污染物部位的平均APC和EC。几乎没有证据表明细菌会重新分布到紧邻但外观清洁的部位。然而，清洗后粪便污染部位的APC和EC残留水平仍显著高于外观清洁部位。将HACCP原则应用于绵羊屠宰和加工表明，可见粪便应通过修剪去除，而预剖腹清洗在去除羊毛方面具有实际且经微生物学验证的作用。在预剖腹清洗前，未受污染部位的APC和EC之间通常具有良好的相关性，这表明在某些情况下，APC可作为胴体总体卫生状况和粪便指示菌存在情况的有用指标。
