Parameter-related process control of disinfection in commercial dishwashers based on functionalized vesicles

IGF 18792 N

Dishwashing processes are defined in hygiene quality management systems on the basis of the Hazard Analysis and Critical Control Points (HACCP) concept as critical control points that must be periodically checked by the company itself. For this purpose, among other things biomonitors are used which have to be evaluated in microbiological laboratories; results are available after 2 days at the earliest. The commissioning of specialist laboratories causes high costs.

Within the scope of the research project, a parameter-related process control based on dye-labelled vesicles was developed, which has various areas, enabling the evaluation of the overall process performance (area 1), the effect of the cleaner chemistry (area 2), the effect of the temperature (area 3) and the removal by the rinsing mechanics (area 4). By adjusting the composition of the membrane lipids, the vesicles were adapted to the chemo- and thermosensitivity of E. faecium and used for the respective areas.

Since the vesicles showed no stability against drying of the normative test soiling RAMS, an inclusion immobilization in alginate matrices was developed. During dishwashing, the respective vesicles were destroyed when the corresponding parameter value was reached, so that the included self-quenched dye calcein was released from the vesicles, which could be easily evaluated by fluorescence staining of the areas.

The good agreement with the normative test specimen according to DIN SPEC 10534 could be confirmed in practical rinsing tests. The results of the project will provide the cleaning service providers with an independently applicable and rapid process control for commercial dishwashing processes.

The research report is available on request from FRT.

The IGF-pro­ject 18792 N of the re­search as­so­ci­a­tion Europäische Forschungs­ge­mein­schaft Reini­gungs- und Hy­gien­etech­nolo­gie e.V., Cam­pus Ficht­en­hain 11, 47807 Krefeld, was sup­port­ed with­in the fund­ing pro­gram „In­dus­trielle Gemein­schafts­forschung und -en­twick­lung (IGF)“ by the Fed­er­al Min­istry of Eco­nom­ic Af­fairs and Cli­mate Ac­tion due to a de­ci­sion of the Ger­man Par­lia­ment.