Table_2.docx

Cold Atmospheric Plasma (CAP) is a promising novel method for biofilm inactivation as log-reduction values up to 4.0 log10 (CFU/cm2) have been reported. Nevertheless, as the efficacy of CAP itself is not sufficient for complete inactivation of mature biofilms, the hurdle technology could be applied in order to obtain higher combined efficacies. In this study, CAP treatment was combined with a mild hydrogen peroxide (H2O2) treatment for disinfection of 1 and 7 day(s) old Listeria monocytogenes and Salmonella Typhimurium biofilms. Three different treatment sequences were investigated in order to determine the most effective treatment sequence, i.e., (i) first CAP, then H2O2, (ii) first H2O2, then CAP, and (iii) a simultaneous treatment of CAP and H2O2. Removal of the biofilm, induction of sub-lethal injury, and H2O2 breakdown due to the presence of catalase within the biofilms were investigated in order to comment on their possible contribution to the combined inactivation efficacy. Results indicated that the preferred treatment sequence was dependent on the biofilm forming species, biofilm age, and applied H2O2 concentration [0.05 or 0.20% (v/v)]. At the lowest H2O2 concentration, the highest log-reductions were generally observed if the CAP treatment was preceded by the H2O2 treatment, while at the highest H2O2 concentration, the opposite sequence (first CAP, then H2O2) proved to be more effective. Induction of sub-lethal injury contributed to the combined bactericidal effect, while the presence of catalase within the biofilms resulted in an increased resistance. In addition, high log-reductions were partially the result of biofilm removal. The highest overall log-reductions [i.e., up to 5.42 ± 0.33 log10 (CFU/cm2)] were obtained at the highest H2O2 concentration if CAP treatment was followed by H2O2 treatment. As this resulted in almost complete inactivation of the L. monocytogenes and S. Typhimurium biofilms, the combined treatment of CAP and H2O2 proved to be a promising method for disinfection of abiotic surfaces.</p

Challenges and Experiences

In the identification of transparency challenges evolving from a discrepancy between needs, state-of-the-art, and experiences that will be discussed, the Strategic Research Agenda (SRA) has utilized a broad range of approaches, including literature analysis, best practice analysis, chain analysis, work group discussions, expert discussions, surveys, web consultations, and simulation studies to reach results that serve the objectives.In this chapter, the focus is on the layer approach, the integrated view follows thereafter. The layer approach distinguishes between. a.upper levels linked to the recipients of transparency andb.lower levels linked to the actors in the food value chain and their production and distribution processes.The different layers identify different communication needs. The lowest level provides the ". infrastructure" for data communication. It is closely related to information technology and the identification of the path that a product takes from production to consumption. This is linked to the tracking and tracing functionality which makes it feasible to communicate additional information as "backpack" on the tracking and tracing information base.The next layer serves the collection of information about the various domains (food safety, food quality, chain integrity) of interest. This layer represents the classical information collection and communication approach. The third layer involves the transformation of information into signals or further to simple-to-understand messages like "this food is safe" which serve the transparency needs of the various stakeholders (consumers, enterprises, and policy) depending on the situation they are in (scenario).</p