Villarreal-Silva Mariana, Genho Daniel P, Ilhak Irfan, Lucia Lisa M, Dickson James S, Gehring Kerri B, Savell Jeffrey W, Castillo Alejandro
Center for Food Safety, Department of Animal Science, Texas Agrilife Research, Texas A&M University, 2471 TAMU, College Station, Texas 77843-2471.
215F Meat Laboratory, Department of Animal Science, Iowa State University, Ames, Iowa 50011-3150, USA.
J Food Prot. 2016 Nov;79(11):1860-1867. doi: 10.4315/0362-028X.JFP-15-481.
Multiple antimicrobial interventions have been validated for use during the beef postharvesting process. However, little has been done to determine the impact of the postharvest environment on pathogen contamination. In this study, surrogate microorganisms were used to simulate pathogen cross-contamination through the postharvest environment at three different abattoirs. At each abattoir, the brisket areas of 13 hide-on carcasses were inoculated after stunning, with a gelatin slurry containing a cocktail (~7 log CFU/ml) of fluorescent Escherichia coli biotype I. These microorganisms are approved as surrogates for E. coli O157:H7 and Salmonella . From these carcasses, samples (300 cm) were taken at different stages during the harvesting process: after hide opening, prior to evisceration, after evisceration, after splitting, and after final intervention. The carcass (noninoculated) immediately following (adjacent to) each hide-inoculated carcass was also tested to determine cross-contamination. Environmental (floor, walls, air) and personal garment (gloves, boots, aprons) samples were collected. Other sampled equipment included knives, meat hooks, hide pullers, and splitting saws. Results demonstrated that cross-contamination occurred between the inoculated hide and the carcass and also by transfer of microorganisms to the adjacent, noninoculated carcasses. Microbial transfer also occurred from hides or carcasses to the environment, personal garments, and equipment. Counts of the surrogate bacteria used were higher in equipment samples (15%) than in environment samples (10%). Personal garments had the lowest occurrence of cross-contamination (7%). For all abattoirs, surrogates were undetected on the carcass (<1.4 log CFU/300cm) after the final intervention stage. This study confirms the importance of following adequate procedures for carcass dressing and highlights an adequate hide opening procedure as a crucial step to prevent carcass contamination.
多种抗菌干预措施已被验证可用于牛肉收获后加工过程。然而，对于收获后环境对病原体污染的影响，人们所做的研究甚少。在本研究中，使用替代微生物模拟在三个不同屠宰场收获后环境中的病原体交叉污染情况。在每个屠宰场，对13头带皮胴体的胸部区域在致昏后接种含有荧光大肠杆菌生物型I混合菌液（约7 log CFU/ml）的明胶浆。这些微生物被批准作为大肠杆菌O157:H7和沙门氏菌的替代物。从这些胴体上，在收获过程的不同阶段采集样本（300平方厘米）：开皮后、去内脏前、去内脏后、劈半后以及最终干预后。紧邻每头接种皮的胴体的下一头（未接种）胴体也进行检测以确定交叉污染情况。采集了环境（地面、墙壁、空气）和个人衣物（手套、靴子、围裙）样本。其他采样设备包括刀具、肉钩、剥皮器和劈半锯。结果表明，接种的皮与胴体之间以及微生物转移到相邻未接种的胴体上均发生了交叉污染。微生物还从皮或胴体转移到环境、个人衣物和设备上。所用替代细菌在设备样本中的计数（15%）高于环境样本（10%）。个人衣物的交叉污染发生率最低（7%）。对于所有屠宰场，在最终干预阶段后，胴体上未检测到替代物（<1.4 log CFU/300平方厘米）。本研究证实了遵循适当的胴体处理程序的重要性，并强调适当的开皮程序是防止胴体污染的关键步骤。
