The photodynamic water treatment with the use of photosensitizers will be shown in the reduction of microbes in simulated wash water. The measurement of oxidative stress or bacterial phenotypic changes will be assessed in correlation with the logarithmic reduction of bacteria upon sanitation with conventional sanitizers.
The fresh produce industry applies washing procedures using sanitizers based on chlorine and peroxides. These compounds can be quickly inactivated by the organic content and in several cases may produce harmful by-products. An alternative approach to the eradication of bacteria is based on the photodynamic water treatment with the use of photosensitizers, which are compounds that can achieve the formation of reactive oxygen species to kill contaminant microbes. In this seminar I will show how the synergy between light and food grade compounds with photosensitizing properties can result in a reduction of microbes in simulated wash water. A second concept of extreme importance to the sanitation of process water is the assessment of the sanitation efficacy. The majority of the assessments does not consider the food matrix's presence or are focused on chemical parameters that are not always correlated with the biological activity against the microbes. I will introduce the concept of measurement of oxidative stress or bacterial phenotypic changes and correlation with the logarithmic reduction of bacteria upon sanitation with conventional sanitizers. This would prove the use of specific probes for oxidative stress or phenotypic changes as quick substitutes for the measurement of the sanitation efficacy.
For more information contact Senior Lecturer in Lifes Sciences Dr Britta Stordal
