Reducing the risk of Salmonella and Listeria using Bactoferm® SM-194 culture
Study objective
Evaluation of the efficacy of Bactoferm® SM-194 in reducing the risk of contamination with Salmonella spp. and Listeria monocytogenes in fermented sausages, by monitoring key parameters: pH, water activity (aw), and reduction in microbial load, throughout the fermentation and drying process.
Bactoferm® SM-194, a solution that offers producers an effective food safety control tool, while maintaining the desired sensory profile.
Methodology
- Intensify the red shade
- Products tested: semi-dry sausage and dry-cured sausage.
- Inoculate with cocktails of Salmonella spp. and Listeria monocytogenes (~2×10⁷ cfu/g).
- Ferment at ~27–32 °C until pH ≤ 5.3.
- Dry to aw ≤ 0.92 (semi-dry) or ≤ 0.89 (raw-dry).
- Monitoring the evolution of pH, aw, and stage-by-stage bacterial reduction.
- Take samples at each critical stage (after fermentation, mid-dry, final dry) for accurate quantification of microbial load and confirmation of log reductions.
Study results
Reducing Salmonella spp.
- In semi-dry sausage (aw < 0.92): ~3.5 log reduction.
- In dry-cured sausage (aw 5 log reduction.
Reducing Listeria monocytogenes
- Until AW ≤ 0.92: >2 log reduction.
- Up to aw ≤ 0.89: >3 log reduction.
Technological parameters
- pH rapidly dropped below 5.3 — due to culture activity.
- Efficient drying, with constant decrease of aw to safe values.
Manufacturer Advantages
- Effective application of the „hurdle technology” concept: acidification + drying + starter culture → high safety.
- Eliminate or significantly reduce risks of Salmonella and Listeria without the need for aggressive added preservatives.
- Ensuring consistent quality between batches (safety + constant sensory profile).
- Possible marketing communication as „safe, controlled product with a high standard of hygiene.”.
The entire process carried out with Bactoferm® SM-194 demonstrates that it is possible to obtain microbiologically safe fermented sausages with a significant reduction (up to ≥ 5 log) of dangerous pathogens, without compromising product quality.
