Combined calorimetric gas- and spore-based biosensor array for online monitoring and sterility assurance of gaseous hydrogen peroxide in aseptic filling machines

A combined calorimetric gas- and spore-based biosensor array is presented in this work to monitor and evaluate the sterilization efficacy of gaseous hydrogen peroxide in aseptic filling machines. H2O2 has been successfully measured under industrial conditions. Furthermore, the effect of H2O2 on three different spore strains , namely Bacillus atrophaeus, Bacillus subtilis and Geobacillus stearothermophilus, has been investigated by means of SEM, AFM and impedimetric measurements. In addition, the sterilization efficacy of a spore-based biosensor and the functioning principle are addressed and discussed: the sensor array is convenient to be used in aseptic food industry to guarantee sterile packages. •A (bio)sensor array to simultaneously monitor gaseous H2O2 and spores' viability is introduced.•Studies of H2O2 on different types of bacterial spores are presented.•Morphological variations of spores can be used as a parameter to determine the viability of spores.•Standard microbiological methods for sterility assurance might be upgraded to (bio)sensor-based technologies.