U.S. Department of Agriculture, Agricultural Research Service, Residue Chemistry and Predictive Microbiology Research Unit, Room 2111, Center for Food Science and Technology, University of Maryland Eastern Shore, Princess Anne, Maryland 21853, USA.
J Food Prot. 2013 Jan;76(1):33-9. doi: 10.4315/0362-028X.JFP-12-224.
The current study was undertaken to acquire data on contamination of chicken parts with Salmonella at retail and to acquire data on cross-contamination of cooked chicken with Salmonella from raw chicken during meal preparation. Whole raw chickens (n = 31) were obtained from local retail stores and cut into two wings, two breasts without skin or bones, two thighs, and two drumsticks. Data for cross-contamination were obtained by cutting up a sterile, cooked chicken breast with the same board and knife used to cut up the raw chicken. The board, knife, and latex gloves used by the food handler were not rinsed or washed before cutting up the sterile, cooked chicken breast, thus providing a worst-case scenario for cross-contamination. Standard curves for the concentration of Salmonella bacteria in 400 ml of buffered peptone water after 6 h of incubation of chicken parts as a function of the initial log number of Salmonella bacteria inoculated onto chicken parts were developed and used to enumerate Salmonella bacteria. Standard curves were not affected by the type of chicken part but did differ (P < 0.05) among the five isolates of Salmonella examined. Consequently, Salmonella bacteria were enumerated on naturally contaminated chicken parts using a standard curve developed with the serotype of Salmonella that was isolated from the original sample. The prevalence of contamination was 3 % (4 of 132), whereas the incidence of cross-contamination was 1.8 % (1 of 57). The positive chicken parts were a thigh from chicken 4, which contained 3 CFU of Salmonella enterica serotype Kentucky, and both wings, one thigh, and one cooked breast portion from chicken 15, which all contained 1 CFU of serotype 8,20:-:z(6). These results indicated that the poultry industry is providing consumers in the studied area with chicken that has a low prevalence and low number of Salmonella bacteria at retail and that has a low incidence and low level of cross-contamination of cooked chicken with Salmonella from raw chicken during meal preparation under a worst-case scenario.
本研究旨在获取鸡肉各部位沙门氏菌污染的数据，并获取生鸡肉在制备餐食过程中对熟鸡肉交叉污染的沙门氏菌数据。从当地零售店购买了 31 只整鸡，将其切成两个翅膀、两个无皮无骨鸡胸、两个大腿和两个鸡腿。通过使用与切割生鸡肉相同的案板和刀具切割无菌熟鸡胸来获取交叉污染的数据。在切割无菌熟鸡胸之前，食品处理人员没有冲洗或清洗案板、刀具和乳胶手套，从而提供了交叉污染的最坏情况。建立了鸡肉各部位在缓冲蛋白胨水中孵育 6 小时后沙门氏菌浓度与初始接种沙门氏菌数量对数的标准曲线，用于计数沙门氏菌。标准曲线不受鸡肉部位类型的影响，但在所检查的 5 株沙门氏菌之间存在差异（P < 0.05）。因此，使用从原始样本中分离出的沙门氏菌血清型建立的标准曲线，对自然污染的鸡肉各部位进行沙门氏菌计数。污染的流行率为 3%（132 个中有 4 个），而交叉污染的发生率为 1.8%（57 个中有 1 个）。阳性鸡肉部位为 4 号鸡的大腿，含有 3 CFU 的肠炎沙门氏菌血清型肯塔基州，以及 15 号鸡的两个翅膀、一个大腿和一个熟鸡胸部位，均含有 1 CFU 的血清型 8,20:-:z(6)。这些结果表明，在所研究地区，家禽业为消费者提供了零售鸡肉，其沙门氏菌污染率和数量较低，在最坏情况下，生鸡肉制备餐食过程中对熟鸡肉的交叉污染发生率和水平也较低。
