Kinetic modeling the survival of Escherichia coli in pickled radish fermentation with different salt concentrations

Abstract

The survival of Escherichia coli in pickled radish fermentation with salt concentrations from 2% to 10% was studied kinetically. The results showed that mostly E. coli first underwent 1–2 days of growth, followed by a decline and finally died off after 4–5 days of fermentation. A kinetic model was developed to reveal how the growth and survival of E. coli were affected by acid content, pH value and salt concentration during the pickle fermentation. Model‐based simulations suggested that moderate salt concentration (4%–9%) resulted in shorter survival period of E. coli. Sensitivity analysis showed that the lowest pH value for E. coli growth played the most important role in determining the peak amount and the survival period of E. coli. This study provides a reference for risk assessment and safe production of pickles and other similar fermented vegetables. Practical Applications This study provides an appropriate salt concentration range for safer production of pickles. The model developed can be a reference for the kinetic analyses and risk assessments of pickle making and other similar fermentation processes.

Fermented vegetables in China: overview, novel processes, influencing factors, lactic acid bacteria and industrialisation status

“…High salt concentrations can inhibit the growth of putrefying bacteria, the formation of harmful chemicals and reduce the risk of spoilage, but can also lead to a reduction in the relative abundance of LAB, resulting in poor‐quality final products (Xiong et al ., 2016). In contrast, lower salt concentrations can increase the relative abundance of LAB, resulting in higher product quality and safety, by inhibiting E. coli growth (Wu et al ., 2023). A study on the effects of different salt concentrations on foodborne pathogenic E. coli O157:H7 and Listeria monocytogenes demonstrated that lower salt concentrations of 1% and 2% resulted in lower survival rates of pathogenic bacteria compared with 3% salt (Kim et al ., 2021).…”