Effect of Simulated Transport Conditions on Microbiological Properties of Bottled Natural Mineral Water

Abstract

Bottled mineral water is distributed globally through complex supply chains, making it available far beyond its bottling plants. In low-viscosity food matrices, invisible changes may occur due to shaking. The primary purpose of this research was to investigate the potential correlation between the intensity of mechanical agitation and the number of detectable microorganisms in bottled mineral water. The simulation of dynamic mechanical vibration was conducted using both time-accelerated and real-time tests. Freshly bottled natural mineral water and commercially available mineral water brands from different bottling locations and times were subjected to random vibration at three intensities as specified by the ASTM D-4169-16 standard, which simulates road transport on semi-trailer trucks. The study investigated the specific growth rate, the generation time, and the maximum cell numbers of microorganisms. The quantitative PCR (qPCR) technique was used to determine and compare the concentrations of microbes. Dynamic mechanical vibration affected the microbiome of mineral waters, influencing growth rates and generation times. In the case of waters from different bottling locations and times, the specific growth rate varied significantly for each water and for each intensity. This finding demonstrates that the microbiome composition of the water source and the interaction between microbes influence the response to mechanical impact. The time-accelerated test was shown to be suitable for analyzing the reaction of the microbiome of the tested matrix to the intensity and duration of vibration. The applied test protocol enabled the monitoring of changes in cell numbers by qPCR. All three intensities of the time-accelerated method were effective in testing the effects of real-time mechanical agitation on the microbiome.