The present study investigated the presence, growth potential, and public health risk posed by Listeria monocytogenes in a ready-to-eat “shrimp cocktail”. The pathogen was detected in 4 out of the 104 samples, and there were no counts above the enumeration limit (1 Log colony-forming unit (CFU)/g); the product was a suitable substrate for pathogen growth owing to its chemical/physical properties. A stochastic quantitative microbial risk assessment (QMRA) was performed to estimate the expected number of invasive listeriosis cases caused by the consumption of 10,000 servings of the product on the last day of its shelf life, considering a population comprising healthy consumers, those susceptible, and transplant recipients. The model predicted no cases for this scenario. Uncertainties were included by considering alternative scenarios; even when considering an increased mean bacterial concentration (up to 3–4 Log CFU/g), no cases were estimated. Following a producer's demand, the exposure assessment model was also used to estimate the probability of the product exceeding the threshold of 2 log CFU/g during the shelf life. The possibility of Listeria growth in the product could not be avoided. Therefore, a modification of the production process was tested to re-classify the product as unsuitable for Listeria growth (EC Reg. 2073/2005). The shrimps were conditioned in three different organic acid solutions comprising: acetic acid (1500 ppm) (A); benzoic acid (1500 ppm) + acetic acid (500 ppm) + lactic acid (750 ppm) (BLA); and lactic acid (4500 ppm) + sodium acetate (2500 ppm) (LSA). Testing was conducted over various treatment durations (1 day–5 days). Treatment for 2 days in the LSA solution was selected based on efficacy, the absence of consumer-perceptible sensorial modifications, and the producers' production rate requirements. The concentration of L. monocytogenes decreased when the new process was applied, which confirmed the usefulness and effectiveness of the treatment relative to the traditional process. Thus, the product obtained by the modified production process did not support the growth of L. monocytogenes.

本研究调查了单核细胞增生李斯特菌的存在，增长潜力和公共卫生风险在即食的“虾鸡尾酒”中。在104个样本中有4个检测到了病原体，没有计数超过计数上限（1个对数菌落形成单位（CFU）/ g）；由于其化学/物理特性，该产品是病原体生长的合适底物。进行了一项随机定量微生物风险评估（QMRA），以估计在其保质期的最后一天食用10,000份产品引起的侵袭性李斯特菌病病例的预期数量，考虑到包括健康消费者，易感人群和移植接受者。该模型没有预测这种情况下的情况。通过考虑替代方案将不确定性包括在内；即使考虑增加平均细菌浓度（高达3–4 Log CFU / g），也没有估计病例。根据生产商的需求，暴露评估模型还用于估计产品在货架期内超过2 log CFU / g阈值的可能性。的可能性产品中的李斯特菌生长无法避免。因此，对生产工艺进行了测试，以将产品重新分类为不适合李斯特菌生长（EC Reg。2073/2005）。将虾在三种不同的有机酸溶液中调理，这些溶液包括：乙酸（1500 ppm）（A）；和 苯甲酸（1500 ppm）+乙酸（500 ppm）+乳酸（750 ppm）（BLA）; 乳酸（4500 ppm）+乙酸钠（2500 ppm）（LSA）。测试在各种治疗持续时间（1天至5天）中进行。根据疗效，是否存在消费者可感知的感觉变化以及生产者对生产率的要求，选择在LSA溶液中处理2天。单核细胞增生李斯特菌的浓度当采用新工艺时，治疗效果下降了，这证实了该治疗相对于传统工艺的有用性和有效性。因此，通过改良的生产方法获得的产物不支持单核细胞增生李斯特菌的生长。