蔬菜中沙门氏菌生长特性的研究

Research of Salmonella growth characteristics in vegetables

以菠菜、香菜和樱桃番茄为实验材料，通过人工回接鼠伤寒沙门氏菌（Salmonella typhimurium），研究沙门氏菌在蔬菜上的生长特性。结果表明，沙门氏菌能够在上述3种蔬菜上侵染并大量繁殖。沙门氏菌在蔬菜上的生长情况受到温度和种类的影响，在25℃时，在樱桃番茄上的沙门氏菌生长量最大，为2．45×10^4cfu／g；而在4℃时，在香菜上生长的沙门氏菌量最大，菌数为7．5×10^3cfu／g。沙门氏菌的繁殖量随回接浓度增大而增大，但＇-3回接浓度大于15cfu／g时，沙门氏菌生长会受到抑制。在回接茵后4~8h会出现一个沙门氏菌繁殖的高峰，随后在8～10h菌数明显下降，说明沙门氏菌一旦侵染蔬菜会在短时间内快速增长，12h后沙门氏菌繁殖量呈明显下降趋势，可能与致腐菌开始大量繁殖导致蔬菜失水、腐烂有关。

Using spinach, coriander and cherry tomato as material, through artificial inoculation Salmonella typhimurium, the growth characteristics of Salmonella in vegetables were studied. The results showed that Salmonella could infect and bloom the above three kinds of vegetables.Salmonella growth in the vegetables were influenced by temperature and species.The maximum number of Salmonella growth at 25℃ reached 2.45 × 10^4cfu/g in cherry tomato, and that at 4℃reached 7,5 ×10^3cfu/g in parsley. Salmonella growth in vegetables also were affected by the concentration of artificial inoculation. Under certain circumstances, the more artificial inoculation concentration ,the more concentration of Salmonella grew.However,when the artificial inoculation concentration was higher than 15cfu/g, Salmonella growth would be inhibited.After inoculation, salmonella bred to reach a peak in 4~8h, decreased significantly in 8-10h,indicating that Salmonella once infected vegetables would rapidly grow in a short time. After 12h, Salmonella reproductive output was significantly decreased, while the bacteria begin to multiply rapidly in vegetables, resulting in their water loss and decay.