Listeria monocytogenes - not only bad but also persistent

TY - JOUR

T1 - Listeria monocytogenes - not only bad but also persistent

AU - Knøchel, Susanne

PY - 2010/8

Y1 - 2010/8

N2 - Listeria monocytogenes continues to be a problem for the food industry. Some strains seem to have a higher virulence potential for invasive disease, but also less virulent strains in high numbers may cause disease in both healthy and immunocompromised persons. Listeria is well-suited to life in a chilled, wet food production such as dairies. Once a survival niche has been established thorough and targeted cleaning and disinfection is needed since the tolerance to external stresses is much more pronounced in biofilm embedded or dry cells compared with planktonic, growing cells. Current predictive models can estimate the growth potential in simpler systems. Complex systems such as cheeses, with multiple interactions and gradients, cannot as yet be handled apart from the situations where conditions are clearly inhibitive to growth. With regards to predictions of inactivation there are many data dealing with healthy cells, but recent research points towards various forms of physiologically challenged cells and corresponding matrices which enable a much higher degree of survival. While L. monocytogenes cannot be completely eradicated well-functioning pre-requisite programs, including environmental monitoring and pasteurisation, should ensure product safety. Production of soft surface-ripened cheeses requires special vigilance.

AB - Listeria monocytogenes continues to be a problem for the food industry. Some strains seem to have a higher virulence potential for invasive disease, but also less virulent strains in high numbers may cause disease in both healthy and immunocompromised persons. Listeria is well-suited to life in a chilled, wet food production such as dairies. Once a survival niche has been established thorough and targeted cleaning and disinfection is needed since the tolerance to external stresses is much more pronounced in biofilm embedded or dry cells compared with planktonic, growing cells. Current predictive models can estimate the growth potential in simpler systems. Complex systems such as cheeses, with multiple interactions and gradients, cannot as yet be handled apart from the situations where conditions are clearly inhibitive to growth. With regards to predictions of inactivation there are many data dealing with healthy cells, but recent research points towards various forms of physiologically challenged cells and corresponding matrices which enable a much higher degree of survival. While L. monocytogenes cannot be completely eradicated well-functioning pre-requisite programs, including environmental monitoring and pasteurisation, should ensure product safety. Production of soft surface-ripened cheeses requires special vigilance.

M3 - Journal article

SN - 0004-9433

VL - 65

SP - 50

EP - 57

JO - Australian Journal of Dairy Technology

JF - Australian Journal of Dairy Technology

IS - 2

ER -