Modelling and Determination of Parameters Influencing the Transfer of Microorganisms from Food Contact Materials

Abstract

The transfer of microorganisms on packaging materials to a contact surface has only been investigated in the context of laboratory-produced spiked packaging products and agar surfaces in small quantities (0.03–0.10%) so far. Correspondingly, this study focused on the localization of microorganisms on/in industrially produced packaging materials and on the establishment of an experimental laboratory set-up to determine and quantify the parameters influencing the microbial transport from surfaces and different layers of packaging materials to contact agar media. We established a simple model to determine the transfer of microorganisms from packaging materials to microbiological agar plates. In order to clarify the transfer of microorganisms within the material, the samples were split horizontally in their z-dimension, and so produced layers (inner layers) were investigated for their microbial transfer. The parameters incubation time, applied weight and bacterial load for the samples were investigated in more detail in the outer layers (front/back) and the inner layers. No significant difference in the microbial transfer was observed between the outer and inner layers of all samples. We indicate a time-dependent transfer to the media and an independence of the transfer from the applied weight. Moreover, the number of transferred microorganisms is not dependent on the bacterial load of the samples.

Fiber-based food packaging materials in view of bacterial growth and survival capacities

“…Our unique study contributes to fulfill this gap of knowledge by investigating the growth and survival of different species in fiber-based packaging materials, especially since all the packaging materials included are actually used in the food packaging sector ( Table 1 ). These materials generally contain low quantities of bacteria per gram ( Hladíková et al, 2015 ; Maitz et al, 2022 ), also supporting the need for growth studies in terms of food safety. Furthermore, our findings show possibilities to improve product safety but also storability and shelf life of both, packaged food and packaging material itself.…”

“…Nevertheless, little is known about the interactions of microorganisms with the surrounding matrix of fiber packaging due to the high diversity of different types of packaging. While factors affecting a potential transfer of bacteria to contact surfaces have already been assessed ( Maitz et al, 2022 ), the knowledge about microbial growth and survival in food packaging materials needs to be extended. Previous research on the interactions of bacteria with fiber-based packaging materials has largely dealt with fermentation strategies to produce energy carriers such as hydrogen and methane ( Ntaikou et al, 2009 ; Brummer et al, 2014 ; Asato et al, 2016 ; Poladyan et al, 2020 ), or bioplastics ( Abdelmalek et al, 2022 ).…”