Application of redox potential measurement based technique for determination of total count in bottled mineral water

Abstract

Mineral water comprises of 44% of the non alcoholicdrinks market in Europe. On average 105 litres of mineral water is consumed each year in Europe per capita. There is a vast number of water borne pathogens that can be present in mineral water e.g. E coli, Salmonella, Cryptosporidiosis, Giardia, Hepatitis. To ensure the protection of consumers the European Union enforced Commission Directive 2003/40/EC of 16 May 2003 establishing the list, concentrationlimits and labeling requirements for the constituents of natural mineral waters and the conditions for using ozone-enriched air for the treatment of natural mineral waters and spring waters. The MicroTester system developed and patented by the researchers of the Department of Food Hygiene (Szent István University, Faculty of Veterinary Science) and Department of Physics and Automatization (Corvinus University, Faculty of Food Science) is based on the detection of change in redox-potential, caused by microbial activity. This method is suitable for significantly reducing the time requirement of microbiological testing. Our present research shows that by the application of redox- potential measurements, we can significantly accelerate the detection of microbes in mineral water. The time requirement of the detection of the presence of microbes in mineral water by the redox potential measurement was 17 hours, by the classical method it was 72 hours. A further advantage of the redox-potential measurement method is the investment cost is almost one third of that of the impedimetric methods and it allows the application of standard culture media.