FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY




An attempt at assessing microbial growth using impedimetry


The development of Microbiological Risk Assessment (MRA) was conditioned by the following factors: application of HACCP system in food industrial plants; fact that consumers prefer fresh and less processed food products, prerequisite to determine the duration of safe storage of various types of food products; changes in the epidemiology of food poisoning and food infections owing to risks resulting from the occurrence of new microorganisms; and lower immunity of more and more people. Besides the classic plate method of analysing the growth of microorganisms in raw materials and dairy products, a method using the phenomenon of impedance can be applied. Such a determination method involving impedimetry includes the assessment of changes in electrical resistance of a bacterial culture medium, which is generated by the growth of various strains of bacteria or by their specific group. The objective of this study was to determine the usefulness of a Bactometer M 64 monitoring system for analysing the growth and survival potential of microorganisms in some modified microbiological mediums. In the research, model products were applied. They were manufactured by modifying a ‘bioMerieux’ medium with lactic acid, sodium chloride, and sodium V nitrate. The experiment was carried out on the Escherichia coli 22. Microbiological analyses were conducted using an impedimetric monitoring system. The results obtained (time of detection) could appear useful for predictive microbiology as they could be successfully applied to determine reactions of microorganisms towards changing conditions in food.


predictive microbiology, impedimetric method, microbiological risk assessment