Department of Food Science and Human Nutrition, University of Florida, Lake Alfred, FL 33850, USA.
Int J Food Microbiol. 2010 Mar 31;138(1-2):78-84. doi: 10.1016/j.ijfoodmicro.2009.12.002. Epub 2009 Dec 18.
Escherichia coli O157:H7 and Salmonella infections have been associated with consumption of a number of fruits and vegetables. Although the fate of E. coli O157:H7 and Salmonella on many of these products is well studied, little is known about their behavior on cut mango and papaya. Mangoes and papayas have been associated with four and two documented outbreaks of salmonellosis, respectively. The objective of this study was to evaluate the fate of E. coli O157:H7 and Salmonella on fresh (4 degrees C, 12 degrees C and 23 degrees C) and frozen (-20 degrees C) cut mangoes and papayas. Cut mangoes and papayas were spot inoculated with either a four-strain or five-strain cocktail of E. coli O157:H7 or Salmonella, respectively. Inoculated samples were air dried, placed in containers and stored at 4+/-2, 12+/-2, 23+/-2 and -20+/-2 degrees C. Samples were enumerated following stomaching on nonselective and selective media at days 0, 1, 3, 5, 7, 10, 14, 21 and 28 (4+/-2 and 12+/-2 degrees C); 0, 1, 3, 5 and 7 (23+/-2 degrees C); and 0, 7, 14, 21, 28, 60, 90, 120, 150 and 180 (-20+/-2 degrees C). Population levels (log CFU/g) of fruit were calculated. E. coli O157:H7 and Salmonella have the potential to grow on temperature-abused fresh cut mangoes and papayas held at 23 degrees C. At 12 degrees C, Salmonella populations can grow on cut mangoes and papayas, however E. coli O157:H7 populations only grew on papayas. E. coli O157:H7 and Salmonella survived for 28 days, at 4 degrees C, on refrigerated mangoes and papayas. E. coli O157:H7 and Salmonella can survive on frozen cut mangoes and papayas for at least 180 days. Fresh and frozen cut mangoes and papayas are potential vectors for E. coli O157:H7 and Salmonella transmission.
大肠杆菌 O157:H7 和沙门氏菌感染与食用多种水果和蔬菜有关。尽管许多研究都很好地研究了这些产品上的大肠杆菌 O157:H7 和沙门氏菌的命运，但对其在切割芒果和木瓜上的行为却知之甚少。芒果和木瓜分别与四起和两起有记录的沙门氏菌病暴发有关。本研究的目的是评估大肠杆菌 O157:H7 和沙门氏菌在新鲜（4°C、12°C 和 23°C）和冷冻（-20°C）切割芒果和木瓜上的命运。将切割的芒果和木瓜分别用大肠杆菌 O157:H7 或沙门氏菌的四株或五株混合菌液点接种。接种样品风干后，放入容器中，在 4+/-2、12+/-2、23+/-2 和-20+/-2°C 下储存。在 0、1、3、5、7、10、14、21 和 28 天（4+/-2 和 12+/-2°C）；0、1、3、5 和 7 天（23+/-2°C）；以及 0、7、14、21、28、60、90、120、150 和 180 天（-20+/-2°C）时，在非选择性和选择性培养基上进行胃内计数后，对样品进行了计数。计算了水果的种群水平（log CFU/g）。大肠杆菌 O157:H7 和沙门氏菌有在 23°C 下放置的温度滥用新鲜切割的芒果和木瓜上生长的潜力。在 12°C 时，沙门氏菌可以在切割的芒果和木瓜上生长，但大肠杆菌 O157:H7 只能在木瓜上生长。大肠杆菌 O157:H7 和沙门氏菌在 4°C 下冷藏的芒果和木瓜上可存活 28 天。大肠杆菌 O157:H7 和沙门氏菌在冷冻切割的芒果和木瓜上至少可存活 180 天。新鲜和冷冻的切割芒果和木瓜是大肠杆菌 O157:H7 和沙门氏菌传播的潜在载体。
