Bucher Oliver, D'Aoust J-Y, Holley Richard A
Department of Food Science, University of Manitoba, Winnipeg, Manitoba, Canada.
Int J Food Microbiol. 2008 May 31;124(2):195-8. doi: 10.1016/j.ijfoodmicro.2008.03.002. Epub 2008 Mar 7.
Raw, frozen chicken nuggets/strips available at retail and prepared at home before consumption have been identified as a significant risk factor in contracting food-borne salmonellosis. Cases of salmonellosis from consumption of these products may be due, in part, to Salmonella strains originating in broiler feed. In this study the thermal resistances of Salmonella strains isolated from chicken nuggets and strips, chicken nugget/strip meat and broiler feed were determined to assess whether they exhibited enhanced thermal resistance. Thermal resistances (D- and z- values) of 7 cocktails (25 isolates, 4 serovars) were determined in commercially prepared irradiation-treated chicken nugget/strip meat blend, and heated in a constant temperature waterbath. The thermal resistances found were lower than those reported for similar strains in the literature. D-values ranged from 6.93 to 0.12 min at 55 and 62 degrees C respectively, with z-values from 4.10 to 5.17 degrees C. Two strains of S. Enteritidis separately isolated from pelleted feed and chicken nugget meat blend, with indistinguishable geno- and phenotypes, had lower (and probably identical) thermal resistances than the other isolates. Results indicated that the strains of Salmonella isolated from raw, frozen chicken nuggets/strips and pelleted broiler feed did not exhibit unusually high thermal resistance, and that normal heating (71 degrees C) prior to consumption should eliminate these organisms from chicken nuggets/strips.
零售的生冻鸡肉块/鸡肉条以及在家烹饪后食用的此类产品已被确定为感染食源性沙门氏菌病的一个重要风险因素。食用这些产品导致的沙门氏菌病病例,部分可能归因于源自肉鸡饲料的沙门氏菌菌株。在本研究中,测定了从鸡肉块和鸡肉条、鸡肉块/鸡肉条肉以及肉鸡饲料中分离出的沙门氏菌菌株的热抗性,以评估它们是否表现出增强的热抗性。在商业制备的经辐照处理的鸡肉块/鸡肉条肉混合物中测定了7种混合菌液(25个分离株,4个血清型)的热抗性(D值和z值),并在恒温水浴中加热。所发现的热抗性低于文献中报道的类似菌株。在55℃和62℃时,D值分别为6.93至0.12分钟,z值为4.10至5.17℃。从颗粒饲料和鸡肉块肉混合物中分别分离出的两株肠炎沙门氏菌,其基因型和表型无法区分,它们的热抗性低于其他分离株(可能相同)。结果表明,从生冻鸡肉块/鸡肉条和颗粒状肉鸡饲料中分离出的沙门氏菌菌株并未表现出异常高的热抗性,并且在食用前进行正常加热(71℃)应能消除鸡肉块/鸡肉条中的这些微生物。