Detection of Foodborne Pathogens and Analysis of Aflatoxin Levels in Home-made Doenjang Samples

Doenjang is a traditional Korean fermented soybean product that provides a major source of protein. In this study, a total of 18 different home-made doenjang samples were examined for the presence of foodborne pathogens and the total aflatoxin levels. Using an enzyme-linked immunosorbent assay to assess microbial quality and potential public health risk, we showed that total coliform levels in the doenjang samples ranged from 0 to 4.43±2.32 ×10(6) CFU/g, and the maximum limit of Bacillus cereus was 4.67±2.0×10(5) CFU/g. However, other foodborne pathogens, such as Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella spp., were not detected among the tested samples. One of the samples (S3) showed a maximum limit of 42.2±9.1 μg/kg for aflatoxin levels, which was above the safety limit allowed by the Codex Alimentarius Commission (CAC) regulatory agency. Further research is necessary to determine whether and how doenjang safety can be improved via elimination/reduction of microbial contamination during fermentation and storage or using microbial starter cultures for its fermentation.