Bosilevac Joseph M, Shackelford Steven D, Brichta Dayna M, Koohmaraie Mohammad
US Department of Agriculture, Agricultural Research Service, Roman L. Hruska US Meat Animal Research Center, Clay Center, Nebraska 68933-0166, USA.
J Food Prot. 2005 Jul;68(7):1393-8. doi: 10.4315/0362-028x-68.7.1393.
The hides of cattle are the primary source of pathogens such as Escherichia coli O157:H7 that contaminate preevisceration carcasses during commercial beef processing. A number of interventions that reduce hide contamination and subsequent carcass contamination are currently being developed. The objective of this study was to determine the efficacy of ozonated and electrolyzed oxidizing (EO) waters to decontaminate beef hides and to compare these treatments with similar washing in water without the active antimicrobial compounds. Cattle hides draped over barrels were used as the model system. Ozonated water (2 ppm) was applied at 4,800 kPa (700 lb in2) and 15 degrees C for 10 s. Alkaline EO water and acidic EO water were sequentially applied at 60 degrees C for 10 s at 4,800 and 1,700 kPa (250 lb in2), respectively. Treatment using ozonated water reduced hide aerobic plate counts by 2.1 log CFU/100 cm2 and reduced Enterobacteriaceae counts by 3.4 log CFU/100 cm2. EO water treatment reduced aerobic plate counts by 3.5 log CFU/100 cm2 and reduced Enterobacteriaceae counts by 4.3 log CFU/100 cm2. Water controls that matched the wash conditions of the ozonated and EO treatments reduced aerobic plate counts by only 0.5 and 1.0 log CFU/100 cm2, respectively, and each reduced Enterobacteriaceae counts by 0.9 log CFU/100 cm2. The prevalence of E. coli O157 on hides was reduced from 89 to 31% following treatment with ozonated water and from 82 to 35% following EO water treatment. Control wash treatments had no significant effect on the prevalence of E. coli O157:H7. These results demonstrate that ozonated and EO waters can be used to decontaminate hides during processing and may be viable treatments for significantly reducing pathogen loads on beef hides, thereby reducing pathogens on beef carcasses.
牛皮是诸如大肠杆菌O157:H7等病原体的主要来源，这些病原体在商业牛肉加工过程中会污染屠宰前的胴体。目前正在研发多种减少牛皮污染及后续胴体污染的干预措施。本研究的目的是确定臭氧水和电解氧化（EO）水对牛肉皮去污的效果，并将这些处理方法与在无活性抗菌化合物的水中进行类似清洗的方法进行比较。覆盖在桶上的牛皮被用作模型系统。臭氧水（2 ppm）在4800 kPa（700 lb/in²）和15摄氏度下施加10秒。碱性EO水和酸性EO水分别在60摄氏度下以4800 kPa和1700 kPa（250 lb/in²）依次施加10秒。使用臭氧水处理可使牛皮需氧平板计数减少2.1 log CFU/100 cm²，肠杆菌科计数减少3.4 log CFU/100 cm²。EO水处理可使需氧平板计数减少3.5 log CFU/100 cm²，肠杆菌科计数减少4.3 log CFU/100 cm²。与臭氧水和EO处理的清洗条件相匹配的水对照分别仅使需氧平板计数减少0.5和1.0 log CFU/100 cm²，且各自使肠杆菌科计数减少0.9 log CFU/100 cm²。用臭氧水处理后，牛皮上大肠杆菌O157的流行率从89%降至31%，用EO水处理后从82%降至35%。对照清洗处理对大肠杆菌O157:H7的流行率没有显著影响。这些结果表明，臭氧水和EO水可用于在加工过程中对牛皮进行去污，并且可能是显著降低牛肉皮上病原体负荷从而减少牛肉胴体上病原体的可行处理方法。
