Investigation of the effect of different soy sauces on the survival of salmonella and listeria monocytogenes in chicken meat

Aim: Understanding the survival capabilities of foodborne pathogens in poultry meat is a critical issue for food safety and public health. In this study, the survival capability of Salmonella and Listeria monocytogenes (L. monocytogenes) in chicken breast meat treated with soy sauce were investigated. Materials and Methods: Chicken breast samples contaminated with the pathogens were divided into three groups: control (C, 0,85% NaCl physiological saline, no sauce), natural fermented soy sauce group (DF), and natural fermented hot soy sauce group (DFA). These groups were stored at two different temperatures (4 °C and 24 °C). The contaminated chicken breast samples [initial bacterial population: Salmonella (average 10⁸ log CFU/g), L. monocytogenes (average 10⁸ log CFU/g)] were put in soy sauce for 24 hours and then stored for six days under refrigeration (4 °C) and at room temperature (24 °C). Results: Both Salmonella and Listeria monocytogenes remained viable in the soy sauce-treated groups until the final day of storage. At 4 °C, the bacterial counts ranged from 4,38 to 4,40 log CFU/g for Salmonella and from 3,38 to 3,51 log CFU/g for L. monocytogenes. At 24 °C, Salmonella levels were between 2,26 and 3,41 log CFU/g, while L. monocytogenes ranged from 3,17 to 3,19 log CFU/g. Notably, pathogens stored at 24 °C exhibited greater sensitivity to soy sauce treatments. In contrast, the untreated control group showed significantly higher bacterial counts at the end of the six-day storage period. At 4 °C, Salmonella reached 7,67 log CFU/g and L. monocytogenes 6,63 log CFU/g, while at 24 °C, the counts were 7,44 log CFU/g for Salmonella and 7,32 log CFU/g for L. monocytogenes. These differences were found statistically significant (P <0,05). Conclusion: The results of this study reveal that soy sauce treatment is not sufficient to completely eliminate Salmonella and L. monocytogenes pathogens in chicken breast meat.