High hydrostatic pressure (HHP; 200 MPa for 15 min), liquid smoke (0.50%, v/v) and freezing (−80 °C, overnight) was used to eliminate Listeria monocytogenes in BHI broth, raw and smoked trout. The bactericidal effect of liquid smoke solutions (L9 and G6), HHP and their combinations was evaluated against L. monocytogenes LO28, EGD-e and 10403S and further continued with the most resistant strain (10403S) to the combined treatment. For first time, a synergistic effect of liquid smoke and HHP was observed and was further enhanced by freezing prior to HHP. The effect of HHP and liquid smoke, prior to freezing was highest in BHI compared to raw and smoked trout. A major synergistic effect of HHP, liquid smoke and freezing was observed, reaching a 5.48 or 1.93 log CFU/g reduction when smoked or raw trout was used respectively. Furthermore, high injury levels occurred, among treatments reaching up to 55.98%.

Industrial relevance

This paper illustrates for first time, the possibility of using a very low pressure in combination with liquid smoke and freezing to eliminate L. monocytogenes. It was demonstrated that treatment of trout samples with liquid smoke followed by freezing prior to pressurization at 200 MPa for 15 min reduced the number of L. monocytogenes by more than 5-log CFU/g. Such a remarkable bacterial inactivation at a very low pressure (compared to common industrial practices) is a significant achievement that could allow production of safer and novel products by HHP at an affordable price, as the cost of equipment manufacture as well as the maintenance and running costs could be reduced substantially at lower operation pressures.

中文翻译：

---

高静水压处理结合液态烟熏和冷冻技术灭活生烟熏和热熏鳟鱼鱼片中的李斯特菌

使用高静水压力（HHP; 200 MPa持续15分钟），烟气（0.50％，v / v）和冷冻（-80°C，过夜）来消除BHI肉汤，生鱼和烟熏鳟鱼中的李斯特菌。熏液溶液（L9和G6）的杀菌作用，HHP和它们的组合物对抗评价L. 菌等LO28，EGD-e和10403S，并继续对组合治疗产生最强的抗性（10403S）。首次观察到烟雾和HHP的协同作用，并在HHP之前冷冻进一步增强。与生鳟鱼和烟熏鳟鱼相比，BHI中HHP和液态烟在冷冻前的影响最高。观察到HHP，烟熏液和冰冻的主要协同作用，分别使用熏制或生鳟鱼时，CFU / g降低了5.48或1.93 log CFU。此外，高伤害水平发生，在治疗中高达55.98％。

行业相关性

本文示出了用于第一次，使用组合的非常低的压力与液体烟雾和冷冻以消除的可能性L. 菌等。已经证实，与处理液烟鳟鱼样品的随后之前在200MPa加压冷冻15分钟减少的数量L. 菌等超过5个对数CFU / g以下。在非常低的压力下（与常规的工业实践相比）如此显着的细菌灭活是一项重大成就，可以使HHP以可承受的价格生产更安全，新颖的产品，同时还降低了设备制造成本以及维护和运行成本在较低的操作压力下，成本可以大大降低。