Castillo A, Lucia L M, Goodson K J, Savell J W, Acuff G R
Institute of Food Science and Engineering, Center for Food Safety, Department of Animal Science, Texas A&M University, College Station 77843-2471, USA.
J Food Prot. 1999 Feb;62(2):146-51. doi: 10.4315/0362-028x-62.2.146.
Hot beef carcass surface regions (outside round, brisket, and clod) contaminated with feces spread over a 5-cm2 (1-in2) area were cleaned using a steam-vacuum spot-cleaning system alone or combined with subsequent sanitizing treatments of hot water (95 degrees C at the nozzle), or warm (55 degrees C) 2% lactic acid spray, or combinations of these two sanitizing methods. These treatments were compared for effectiveness in reducing aerobic plate counts (APC) and counts of Enterobacteriaceae, total coliforms, thermotolerant coliforms, and Escherichia coli. All treatments significantly reduced the numbers of each group of bacteria on beef carcass surfaces. However, reductions obtained by steam vacuuming were significantly smaller than those obtained by a combination of steam vacuuming with any sanitizing treatment. No differences in bacterial reductions were observed between different carcass surface regions. Steam vacuuming reduced the number of different indicator organisms tested by ca. 3.0 log cycles but also spread the bacterial contamination to areas of the carcass surface adjacent to the contaminated sites. This relocated contamination after steam vacuuming was most effectively reduced by spraying with hot water and then lactic acid. This combined treatment consistently reduced the numbers of Enterobacteriaceae, total and thermotolerant coliforms, and E. coli to undetectable levels (<1.0 log10 CFU/cm2) on areas outside the initial 5-cm2 inoculated areas.
对热牛肉胴体表面被粪便污染且分布在5平方厘米（1平方英寸）区域的部位（外圆、胸肉和颈肉），单独使用蒸汽真空局部清洁系统进行清洁，或结合随后的热水（喷嘴处95摄氏度）消毒处理、温热（55摄氏度）2%乳酸喷雾消毒处理，或这两种消毒方法的组合进行处理。比较这些处理方法在减少需氧平板计数（APC）以及肠杆菌科、总大肠菌群、耐热大肠菌群和大肠杆菌计数方面的效果。所有处理均显著降低了牛肉胴体表面每组细菌的数量。然而，蒸汽真空清洁所获得的细菌数量减少幅度明显小于蒸汽真空清洁与任何消毒处理相结合所获得的减少幅度。在不同的胴体表面区域之间未观察到细菌减少量的差异。蒸汽真空清洁使所测试的不同指示微生物数量减少了约3.0个对数循环，但也将细菌污染扩散到了胴体表面与污染部位相邻的区域。通过先用热水喷雾然后用乳酸喷雾的方式，能最有效地减少蒸汽真空清洁后这种重新分布的污染。这种联合处理持续将初始5平方厘米接种区域以外的区域的肠杆菌科、总大肠菌群、耐热大肠菌群和大肠杆菌数量降低到检测不到的水平（<1.0 log10 CFU/平方厘米）。
